1 /*
2 * ng_base.c
3 */
4
5 /*-
6 * Copyright (c) 1996-1999 Whistle Communications, Inc.
7 * All rights reserved.
8 *
9 * Subject to the following obligations and disclaimer of warranty, use and
10 * redistribution of this software, in source or object code forms, with or
11 * without modifications are expressly permitted by Whistle Communications;
12 * provided, however, that:
13 * 1. Any and all reproductions of the source or object code must include the
14 * copyright notice above and the following disclaimer of warranties; and
15 * 2. No rights are granted, in any manner or form, to use Whistle
16 * Communications, Inc. trademarks, including the mark "WHISTLE
17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
18 * such appears in the above copyright notice or in the software.
19 *
20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
36 * OF SUCH DAMAGE.
37 *
38 * Authors: Julian Elischer <julian@freebsd.org>
39 * Archie Cobbs <archie@freebsd.org>
40 *
41 * $FreeBSD$
42 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $
43 */
44
45 /*
46 * This file implements the base netgraph code.
47 */
48
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/ctype.h>
52 #include <sys/errno.h>
53 #include <sys/kdb.h>
54 #include <sys/kernel.h>
55 #include <sys/ktr.h>
56 #include <sys/limits.h>
57 #include <sys/malloc.h>
58 #include <sys/mbuf.h>
59 #include <sys/queue.h>
60 #include <sys/sysctl.h>
61 #include <sys/syslog.h>
62 #include <sys/refcount.h>
63
64 #include <net/netisr.h>
65
66 #include <netgraph/ng_message.h>
67 #include <netgraph/netgraph.h>
68 #include <netgraph/ng_parse.h>
69
70 MODULE_VERSION(netgraph, NG_ABI_VERSION);
71
72 /* List of all active nodes */
73 static LIST_HEAD(, ng_node) ng_nodelist;
74 static struct mtx ng_nodelist_mtx;
75
76 /* Mutex to protect topology events. */
77 static struct mtx ng_topo_mtx;
78
79 #ifdef NETGRAPH_DEBUG
80 static struct mtx ngq_mtx; /* protects the queue item list */
81
82 static SLIST_HEAD(, ng_node) ng_allnodes;
83 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */
84 static SLIST_HEAD(, ng_hook) ng_allhooks;
85 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */
86
87 static void ng_dumpitems(void);
88 static void ng_dumpnodes(void);
89 static void ng_dumphooks(void);
90
91 #endif /* NETGRAPH_DEBUG */
92 /*
93 * DEAD versions of the structures.
94 * In order to avoid races, it is sometimes neccesary to point
95 * at SOMETHING even though theoretically, the current entity is
96 * INVALID. Use these to avoid these races.
97 */
98 struct ng_type ng_deadtype = {
99 NG_ABI_VERSION,
100 "dead",
101 NULL, /* modevent */
102 NULL, /* constructor */
103 NULL, /* rcvmsg */
104 NULL, /* shutdown */
105 NULL, /* newhook */
106 NULL, /* findhook */
107 NULL, /* connect */
108 NULL, /* rcvdata */
109 NULL, /* disconnect */
110 NULL, /* cmdlist */
111 };
112
113 struct ng_node ng_deadnode = {
114 "dead",
115 &ng_deadtype,
116 NGF_INVALID,
117 1, /* refs */
118 0, /* numhooks */
119 NULL, /* private */
120 0, /* ID */
121 LIST_HEAD_INITIALIZER(ng_deadnode.hooks),
122 {}, /* all_nodes list entry */
123 {}, /* id hashtable list entry */
124 {}, /* workqueue entry */
125 { 0,
126 {}, /* should never use! (should hang) */
127 NULL,
128 &ng_deadnode.nd_input_queue.queue,
129 &ng_deadnode
130 },
131 #ifdef NETGRAPH_DEBUG
132 ND_MAGIC,
133 __FILE__,
134 __LINE__,
135 {NULL}
136 #endif /* NETGRAPH_DEBUG */
137 };
138
139 struct ng_hook ng_deadhook = {
140 "dead",
141 NULL, /* private */
142 HK_INVALID | HK_DEAD,
143 1, /* refs always >= 1 */
144 0, /* undefined data link type */
145 &ng_deadhook, /* Peer is self */
146 &ng_deadnode, /* attached to deadnode */
147 {}, /* hooks list */
148 NULL, /* override rcvmsg() */
149 NULL, /* override rcvdata() */
150 #ifdef NETGRAPH_DEBUG
151 HK_MAGIC,
152 __FILE__,
153 __LINE__,
154 {NULL}
155 #endif /* NETGRAPH_DEBUG */
156 };
157
158 /*
159 * END DEAD STRUCTURES
160 */
161 /* List nodes with unallocated work */
162 static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist);
163 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */
164
165 /* List of installed types */
166 static LIST_HEAD(, ng_type) ng_typelist;
167 static struct mtx ng_typelist_mtx;
168
169 /* Hash related definitions */
170 /* XXX Don't need to initialise them because it's a LIST */
171 #define NG_ID_HASH_SIZE 32 /* most systems wont need even this many */
172 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE];
173 static struct mtx ng_idhash_mtx;
174 /* Method to find a node.. used twice so do it here */
175 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE))
176 #define NG_IDHASH_FIND(ID, node) \
177 do { \
178 mtx_assert(&ng_idhash_mtx, MA_OWNED); \
179 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \
180 nd_idnodes) { \
181 if (NG_NODE_IS_VALID(node) \
182 && (NG_NODE_ID(node) == ID)) { \
183 break; \
184 } \
185 } \
186 } while (0)
187
188
189 /* Internal functions */
190 static int ng_add_hook(node_p node, const char *name, hook_p * hookp);
191 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook);
192 static ng_ID_t ng_decodeidname(const char *name);
193 static int ngb_mod_event(module_t mod, int event, void *data);
194 static void ng_worklist_remove(node_p node);
195 static void ngintr(void);
196 static int ng_apply_item(node_p node, item_p item, int rw);
197 static void ng_flush_input_queue(struct ng_queue * ngq);
198 static void ng_setisr(node_p node);
199 static node_p ng_ID2noderef(ng_ID_t ID);
200 static int ng_con_nodes(item_p item, node_p node, const char *name,
201 node_p node2, const char *name2);
202 static int ng_con_part2(node_p node, item_p item, hook_p hook);
203 static int ng_con_part3(node_p node, item_p item, hook_p hook);
204 static int ng_mkpeer(node_p node, const char *name,
205 const char *name2, char *type);
206
207 /* Imported, these used to be externally visible, some may go back. */
208 void ng_destroy_hook(hook_p hook);
209 node_p ng_name2noderef(node_p node, const char *name);
210 int ng_path2noderef(node_p here, const char *path,
211 node_p *dest, hook_p *lasthook);
212 int ng_make_node(const char *type, node_p *nodepp);
213 int ng_path_parse(char *addr, char **node, char **path, char **hook);
214 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3);
215 void ng_unname(node_p node);
216
217
218 /* Our own netgraph malloc type */
219 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages");
220 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures");
221 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures");
222 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures");
223 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage");
224
225 /* Should not be visible outside this file */
226
227 #define _NG_ALLOC_HOOK(hook) \
228 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO)
229 #define _NG_ALLOC_NODE(node) \
230 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO)
231
232 #define NG_QUEUE_LOCK_INIT(n) \
233 mtx_init(&(n)->q_mtx, "ng_node", NULL, MTX_DEF)
234 #define NG_QUEUE_LOCK(n) \
235 mtx_lock(&(n)->q_mtx)
236 #define NG_QUEUE_UNLOCK(n) \
237 mtx_unlock(&(n)->q_mtx)
238 #define NG_WORKLIST_LOCK_INIT() \
239 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_DEF)
240 #define NG_WORKLIST_LOCK() \
241 mtx_lock(&ng_worklist_mtx)
242 #define NG_WORKLIST_UNLOCK() \
243 mtx_unlock(&ng_worklist_mtx)
244
245 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
246 /*
247 * In debug mode:
248 * In an attempt to help track reference count screwups
249 * we do not free objects back to the malloc system, but keep them
250 * in a local cache where we can examine them and keep information safely
251 * after they have been freed.
252 * We use this scheme for nodes and hooks, and to some extent for items.
253 */
254 static __inline hook_p
255 ng_alloc_hook(void)
256 {
257 hook_p hook;
258 SLIST_ENTRY(ng_hook) temp;
259 mtx_lock(&ng_nodelist_mtx);
260 hook = LIST_FIRST(&ng_freehooks);
261 if (hook) {
262 LIST_REMOVE(hook, hk_hooks);
263 bcopy(&hook->hk_all, &temp, sizeof(temp));
264 bzero(hook, sizeof(struct ng_hook));
265 bcopy(&temp, &hook->hk_all, sizeof(temp));
266 mtx_unlock(&ng_nodelist_mtx);
267 hook->hk_magic = HK_MAGIC;
268 } else {
269 mtx_unlock(&ng_nodelist_mtx);
270 _NG_ALLOC_HOOK(hook);
271 if (hook) {
272 hook->hk_magic = HK_MAGIC;
273 mtx_lock(&ng_nodelist_mtx);
274 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all);
275 mtx_unlock(&ng_nodelist_mtx);
276 }
277 }
278 return (hook);
279 }
280
281 static __inline node_p
282 ng_alloc_node(void)
283 {
284 node_p node;
285 SLIST_ENTRY(ng_node) temp;
286 mtx_lock(&ng_nodelist_mtx);
287 node = LIST_FIRST(&ng_freenodes);
288 if (node) {
289 LIST_REMOVE(node, nd_nodes);
290 bcopy(&node->nd_all, &temp, sizeof(temp));
291 bzero(node, sizeof(struct ng_node));
292 bcopy(&temp, &node->nd_all, sizeof(temp));
293 mtx_unlock(&ng_nodelist_mtx);
294 node->nd_magic = ND_MAGIC;
295 } else {
296 mtx_unlock(&ng_nodelist_mtx);
297 _NG_ALLOC_NODE(node);
298 if (node) {
299 node->nd_magic = ND_MAGIC;
300 mtx_lock(&ng_nodelist_mtx);
301 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all);
302 mtx_unlock(&ng_nodelist_mtx);
303 }
304 }
305 return (node);
306 }
307
308 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0)
309 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0)
310
311
312 #define NG_FREE_HOOK(hook) \
313 do { \
314 mtx_lock(&ng_nodelist_mtx); \
315 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \
316 hook->hk_magic = 0; \
317 mtx_unlock(&ng_nodelist_mtx); \
318 } while (0)
319
320 #define NG_FREE_NODE(node) \
321 do { \
322 mtx_lock(&ng_nodelist_mtx); \
323 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \
324 node->nd_magic = 0; \
325 mtx_unlock(&ng_nodelist_mtx); \
326 } while (0)
327
328 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
329
330 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook)
331 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node)
332
333 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0)
334 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0)
335
336 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
337
338 /* Set this to kdb_enter("X") to catch all errors as they occur */
339 #ifndef TRAP_ERROR
340 #define TRAP_ERROR()
341 #endif
342
343 static ng_ID_t nextID = 1;
344
345 #ifdef INVARIANTS
346 #define CHECK_DATA_MBUF(m) do { \
347 struct mbuf *n; \
348 int total; \
349 \
350 M_ASSERTPKTHDR(m); \
351 for (total = 0, n = (m); n != NULL; n = n->m_next) { \
352 total += n->m_len; \
353 if (n->m_nextpkt != NULL) \
354 panic("%s: m_nextpkt", __func__); \
355 } \
356 \
357 if ((m)->m_pkthdr.len != total) { \
358 panic("%s: %d != %d", \
359 __func__, (m)->m_pkthdr.len, total); \
360 } \
361 } while (0)
362 #else
363 #define CHECK_DATA_MBUF(m)
364 #endif
365
366 #define ERROUT(x) do { error = (x); goto done; } while (0)
367
368 /************************************************************************
369 Parse type definitions for generic messages
370 ************************************************************************/
371
372 /* Handy structure parse type defining macro */
373 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \
374 static const struct ng_parse_struct_field \
375 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \
376 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \
377 &ng_parse_struct_type, \
378 &ng_ ## lo ## _type_fields \
379 }
380
381 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ());
382 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ());
383 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ());
384 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ());
385 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ());
386 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ());
387 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type));
388
389 /* Get length of an array when the length is stored as a 32 bit
390 value immediately preceding the array -- as with struct namelist
391 and struct typelist. */
392 static int
393 ng_generic_list_getLength(const struct ng_parse_type *type,
394 const u_char *start, const u_char *buf)
395 {
396 return *((const u_int32_t *)(buf - 4));
397 }
398
399 /* Get length of the array of struct linkinfo inside a struct hooklist */
400 static int
401 ng_generic_linkinfo_getLength(const struct ng_parse_type *type,
402 const u_char *start, const u_char *buf)
403 {
404 const struct hooklist *hl = (const struct hooklist *)start;
405
406 return hl->nodeinfo.hooks;
407 }
408
409 /* Array type for a variable length array of struct namelist */
410 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = {
411 &ng_generic_nodeinfo_type,
412 &ng_generic_list_getLength
413 };
414 static const struct ng_parse_type ng_generic_nodeinfoarray_type = {
415 &ng_parse_array_type,
416 &ng_nodeinfoarray_type_info
417 };
418
419 /* Array type for a variable length array of struct typelist */
420 static const struct ng_parse_array_info ng_typeinfoarray_type_info = {
421 &ng_generic_typeinfo_type,
422 &ng_generic_list_getLength
423 };
424 static const struct ng_parse_type ng_generic_typeinfoarray_type = {
425 &ng_parse_array_type,
426 &ng_typeinfoarray_type_info
427 };
428
429 /* Array type for array of struct linkinfo in struct hooklist */
430 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = {
431 &ng_generic_linkinfo_type,
432 &ng_generic_linkinfo_getLength
433 };
434 static const struct ng_parse_type ng_generic_linkinfo_array_type = {
435 &ng_parse_array_type,
436 &ng_generic_linkinfo_array_type_info
437 };
438
439 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type));
440 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST,
441 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type));
442 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES,
443 (&ng_generic_nodeinfoarray_type));
444
445 /* List of commands and how to convert arguments to/from ASCII */
446 static const struct ng_cmdlist ng_generic_cmds[] = {
447 {
448 NGM_GENERIC_COOKIE,
449 NGM_SHUTDOWN,
450 "shutdown",
451 NULL,
452 NULL
453 },
454 {
455 NGM_GENERIC_COOKIE,
456 NGM_MKPEER,
457 "mkpeer",
458 &ng_generic_mkpeer_type,
459 NULL
460 },
461 {
462 NGM_GENERIC_COOKIE,
463 NGM_CONNECT,
464 "connect",
465 &ng_generic_connect_type,
466 NULL
467 },
468 {
469 NGM_GENERIC_COOKIE,
470 NGM_NAME,
471 "name",
472 &ng_generic_name_type,
473 NULL
474 },
475 {
476 NGM_GENERIC_COOKIE,
477 NGM_RMHOOK,
478 "rmhook",
479 &ng_generic_rmhook_type,
480 NULL
481 },
482 {
483 NGM_GENERIC_COOKIE,
484 NGM_NODEINFO,
485 "nodeinfo",
486 NULL,
487 &ng_generic_nodeinfo_type
488 },
489 {
490 NGM_GENERIC_COOKIE,
491 NGM_LISTHOOKS,
492 "listhooks",
493 NULL,
494 &ng_generic_hooklist_type
495 },
496 {
497 NGM_GENERIC_COOKIE,
498 NGM_LISTNAMES,
499 "listnames",
500 NULL,
501 &ng_generic_listnodes_type /* same as NGM_LISTNODES */
502 },
503 {
504 NGM_GENERIC_COOKIE,
505 NGM_LISTNODES,
506 "listnodes",
507 NULL,
508 &ng_generic_listnodes_type
509 },
510 {
511 NGM_GENERIC_COOKIE,
512 NGM_LISTTYPES,
513 "listtypes",
514 NULL,
515 &ng_generic_typeinfo_type
516 },
517 {
518 NGM_GENERIC_COOKIE,
519 NGM_TEXT_CONFIG,
520 "textconfig",
521 NULL,
522 &ng_parse_string_type
523 },
524 {
525 NGM_GENERIC_COOKIE,
526 NGM_TEXT_STATUS,
527 "textstatus",
528 NULL,
529 &ng_parse_string_type
530 },
531 {
532 NGM_GENERIC_COOKIE,
533 NGM_ASCII2BINARY,
534 "ascii2binary",
535 &ng_parse_ng_mesg_type,
536 &ng_parse_ng_mesg_type
537 },
538 {
539 NGM_GENERIC_COOKIE,
540 NGM_BINARY2ASCII,
541 "binary2ascii",
542 &ng_parse_ng_mesg_type,
543 &ng_parse_ng_mesg_type
544 },
545 { 0 }
546 };
547
548 /************************************************************************
549 Node routines
550 ************************************************************************/
551
552 /*
553 * Instantiate a node of the requested type
554 */
555 int
556 ng_make_node(const char *typename, node_p *nodepp)
557 {
558 struct ng_type *type;
559 int error;
560
561 /* Check that the type makes sense */
562 if (typename == NULL) {
563 TRAP_ERROR();
564 return (EINVAL);
565 }
566
567 /* Locate the node type. If we fail we return. Do not try to load
568 * module.
569 */
570 if ((type = ng_findtype(typename)) == NULL)
571 return (ENXIO);
572
573 /*
574 * If we have a constructor, then make the node and
575 * call the constructor to do type specific initialisation.
576 */
577 if (type->constructor != NULL) {
578 if ((error = ng_make_node_common(type, nodepp)) == 0) {
579 if ((error = ((*type->constructor)(*nodepp)) != 0)) {
580 NG_NODE_UNREF(*nodepp);
581 }
582 }
583 } else {
584 /*
585 * Node has no constructor. We cannot ask for one
586 * to be made. It must be brought into existence by
587 * some external agency. The external agency should
588 * call ng_make_node_common() directly to get the
589 * netgraph part initialised.
590 */
591 TRAP_ERROR();
592 error = EINVAL;
593 }
594 return (error);
595 }
596
597 /*
598 * Generic node creation. Called by node initialisation for externally
599 * instantiated nodes (e.g. hardware, sockets, etc ).
600 * The returned node has a reference count of 1.
601 */
602 int
603 ng_make_node_common(struct ng_type *type, node_p *nodepp)
604 {
605 node_p node;
606
607 /* Require the node type to have been already installed */
608 if (ng_findtype(type->name) == NULL) {
609 TRAP_ERROR();
610 return (EINVAL);
611 }
612
613 /* Make a node and try attach it to the type */
614 NG_ALLOC_NODE(node);
615 if (node == NULL) {
616 TRAP_ERROR();
617 return (ENOMEM);
618 }
619 node->nd_type = type;
620 NG_NODE_REF(node); /* note reference */
621 type->refs++;
622
623 NG_QUEUE_LOCK_INIT(&node->nd_input_queue);
624 node->nd_input_queue.queue = NULL;
625 node->nd_input_queue.last = &node->nd_input_queue.queue;
626 node->nd_input_queue.q_flags = 0;
627 node->nd_input_queue.q_node = node;
628
629 /* Initialize hook list for new node */
630 LIST_INIT(&node->nd_hooks);
631
632 /* Link us into the node linked list */
633 mtx_lock(&ng_nodelist_mtx);
634 LIST_INSERT_HEAD(&ng_nodelist, node, nd_nodes);
635 mtx_unlock(&ng_nodelist_mtx);
636
637
638 /* get an ID and put us in the hash chain */
639 mtx_lock(&ng_idhash_mtx);
640 for (;;) { /* wrap protection, even if silly */
641 node_p node2 = NULL;
642 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */
643
644 /* Is there a problem with the new number? */
645 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */
646 if ((node->nd_ID != 0) && (node2 == NULL)) {
647 break;
648 }
649 }
650 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)],
651 node, nd_idnodes);
652 mtx_unlock(&ng_idhash_mtx);
653
654 /* Done */
655 *nodepp = node;
656 return (0);
657 }
658
659 /*
660 * Forceably start the shutdown process on a node. Either call
661 * its shutdown method, or do the default shutdown if there is
662 * no type-specific method.
663 *
664 * We can only be called from a shutdown message, so we know we have
665 * a writer lock, and therefore exclusive access. It also means
666 * that we should not be on the work queue, but we check anyhow.
667 *
668 * Persistent node types must have a type-specific method which
669 * allocates a new node in which case, this one is irretrievably going away,
670 * or cleans up anything it needs, and just makes the node valid again,
671 * in which case we allow the node to survive.
672 *
673 * XXX We need to think of how to tell a persistent node that we
674 * REALLY need to go away because the hardware has gone or we
675 * are rebooting.... etc.
676 */
677 void
678 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3)
679 {
680 hook_p hook;
681
682 /* Check if it's already shutting down */
683 if ((node->nd_flags & NGF_CLOSING) != 0)
684 return;
685
686 if (node == &ng_deadnode) {
687 printf ("shutdown called on deadnode\n");
688 return;
689 }
690
691 /* Add an extra reference so it doesn't go away during this */
692 NG_NODE_REF(node);
693
694 /*
695 * Mark it invalid so any newcomers know not to try use it
696 * Also add our own mark so we can't recurse
697 * note that NGF_INVALID does not do this as it's also set during
698 * creation
699 */
700 node->nd_flags |= NGF_INVALID|NGF_CLOSING;
701
702 /* If node has its pre-shutdown method, then call it first*/
703 if (node->nd_type && node->nd_type->close)
704 (*node->nd_type->close)(node);
705
706 /* Notify all remaining connected nodes to disconnect */
707 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL)
708 ng_destroy_hook(hook);
709
710 /*
711 * Drain the input queue forceably.
712 * it has no hooks so what's it going to do, bleed on someone?
713 * Theoretically we came here from a queue entry that was added
714 * Just before the queue was closed, so it should be empty anyway.
715 * Also removes us from worklist if needed.
716 */
717 ng_flush_input_queue(&node->nd_input_queue);
718
719 /* Ask the type if it has anything to do in this case */
720 if (node->nd_type && node->nd_type->shutdown) {
721 (*node->nd_type->shutdown)(node);
722 if (NG_NODE_IS_VALID(node)) {
723 /*
724 * Well, blow me down if the node code hasn't declared
725 * that it doesn't want to die.
726 * Presumably it is a persistant node.
727 * If we REALLY want it to go away,
728 * e.g. hardware going away,
729 * Our caller should set NGF_REALLY_DIE in nd_flags.
730 */
731 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING);
732 NG_NODE_UNREF(node); /* Assume they still have theirs */
733 return;
734 }
735 } else { /* do the default thing */
736 NG_NODE_UNREF(node);
737 }
738
739 ng_unname(node); /* basically a NOP these days */
740
741 /*
742 * Remove extra reference, possibly the last
743 * Possible other holders of references may include
744 * timeout callouts, but theoretically the node's supposed to
745 * have cancelled them. Possibly hardware dependencies may
746 * force a driver to 'linger' with a reference.
747 */
748 NG_NODE_UNREF(node);
749 }
750
751 /*
752 * Remove a reference to the node, possibly the last.
753 * deadnode always acts as it it were the last.
754 */
755 int
756 ng_unref_node(node_p node)
757 {
758 int v;
759
760 if (node == &ng_deadnode) {
761 return (0);
762 }
763
764 do {
765 v = node->nd_refs - 1;
766 } while (! atomic_cmpset_int(&node->nd_refs, v + 1, v));
767
768 if (v == 0) { /* we were the last */
769
770 mtx_lock(&ng_nodelist_mtx);
771 node->nd_type->refs--; /* XXX maybe should get types lock? */
772 LIST_REMOVE(node, nd_nodes);
773 mtx_unlock(&ng_nodelist_mtx);
774
775 mtx_lock(&ng_idhash_mtx);
776 LIST_REMOVE(node, nd_idnodes);
777 mtx_unlock(&ng_idhash_mtx);
778
779 mtx_destroy(&node->nd_input_queue.q_mtx);
780 NG_FREE_NODE(node);
781 }
782 return (v);
783 }
784
785 /************************************************************************
786 Node ID handling
787 ************************************************************************/
788 static node_p
789 ng_ID2noderef(ng_ID_t ID)
790 {
791 node_p node;
792 mtx_lock(&ng_idhash_mtx);
793 NG_IDHASH_FIND(ID, node);
794 if(node)
795 NG_NODE_REF(node);
796 mtx_unlock(&ng_idhash_mtx);
797 return(node);
798 }
799
800 ng_ID_t
801 ng_node2ID(node_p node)
802 {
803 return (node ? NG_NODE_ID(node) : 0);
804 }
805
806 /************************************************************************
807 Node name handling
808 ************************************************************************/
809
810 /*
811 * Assign a node a name. Once assigned, the name cannot be changed.
812 */
813 int
814 ng_name_node(node_p node, const char *name)
815 {
816 int i;
817 node_p node2;
818
819 /* Check the name is valid */
820 for (i = 0; i < NG_NODESIZ; i++) {
821 if (name[i] == '\0' || name[i] == '.' || name[i] == ':')
822 break;
823 }
824 if (i == 0 || name[i] != '\0') {
825 TRAP_ERROR();
826 return (EINVAL);
827 }
828 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */
829 TRAP_ERROR();
830 return (EINVAL);
831 }
832
833 /* Check the name isn't already being used */
834 if ((node2 = ng_name2noderef(node, name)) != NULL) {
835 NG_NODE_UNREF(node2);
836 TRAP_ERROR();
837 return (EADDRINUSE);
838 }
839
840 /* copy it */
841 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ);
842
843 return (0);
844 }
845
846 /*
847 * Find a node by absolute name. The name should NOT end with ':'
848 * The name "." means "this node" and "[xxx]" means "the node
849 * with ID (ie, at address) xxx".
850 *
851 * Returns the node if found, else NULL.
852 * Eventually should add something faster than a sequential search.
853 * Note it acquires a reference on the node so you can be sure it's still
854 * there.
855 */
856 node_p
857 ng_name2noderef(node_p here, const char *name)
858 {
859 node_p node;
860 ng_ID_t temp;
861
862 /* "." means "this node" */
863 if (strcmp(name, ".") == 0) {
864 NG_NODE_REF(here);
865 return(here);
866 }
867
868 /* Check for name-by-ID */
869 if ((temp = ng_decodeidname(name)) != 0) {
870 return (ng_ID2noderef(temp));
871 }
872
873 /* Find node by name */
874 mtx_lock(&ng_nodelist_mtx);
875 LIST_FOREACH(node, &ng_nodelist, nd_nodes) {
876 if (NG_NODE_IS_VALID(node)
877 && NG_NODE_HAS_NAME(node)
878 && (strcmp(NG_NODE_NAME(node), name) == 0)) {
879 break;
880 }
881 }
882 if (node)
883 NG_NODE_REF(node);
884 mtx_unlock(&ng_nodelist_mtx);
885 return (node);
886 }
887
888 /*
889 * Decode an ID name, eg. "[f03034de]". Returns 0 if the
890 * string is not valid, otherwise returns the value.
891 */
892 static ng_ID_t
893 ng_decodeidname(const char *name)
894 {
895 const int len = strlen(name);
896 char *eptr;
897 u_long val;
898
899 /* Check for proper length, brackets, no leading junk */
900 if ((len < 3)
901 || (name[0] != '[')
902 || (name[len - 1] != ']')
903 || (!isxdigit(name[1]))) {
904 return ((ng_ID_t)0);
905 }
906
907 /* Decode number */
908 val = strtoul(name + 1, &eptr, 16);
909 if ((eptr - name != len - 1)
910 || (val == ULONG_MAX)
911 || (val == 0)) {
912 return ((ng_ID_t)0);
913 }
914 return (ng_ID_t)val;
915 }
916
917 /*
918 * Remove a name from a node. This should only be called
919 * when shutting down and removing the node.
920 * IF we allow name changing this may be more resurrected.
921 */
922 void
923 ng_unname(node_p node)
924 {
925 }
926
927 /************************************************************************
928 Hook routines
929 Names are not optional. Hooks are always connected, except for a
930 brief moment within these routines. On invalidation or during creation
931 they are connected to the 'dead' hook.
932 ************************************************************************/
933
934 /*
935 * Remove a hook reference
936 */
937 void
938 ng_unref_hook(hook_p hook)
939 {
940 int v;
941
942 if (hook == &ng_deadhook) {
943 return;
944 }
945 do {
946 v = hook->hk_refs;
947 } while (! atomic_cmpset_int(&hook->hk_refs, v, v - 1));
948
949 if (v == 1) { /* we were the last */
950 if (_NG_HOOK_NODE(hook)) { /* it'll probably be ng_deadnode */
951 _NG_NODE_UNREF((_NG_HOOK_NODE(hook)));
952 hook->hk_node = NULL;
953 }
954 NG_FREE_HOOK(hook);
955 }
956 }
957
958 /*
959 * Add an unconnected hook to a node. Only used internally.
960 * Assumes node is locked. (XXX not yet true )
961 */
962 static int
963 ng_add_hook(node_p node, const char *name, hook_p *hookp)
964 {
965 hook_p hook;
966 int error = 0;
967
968 /* Check that the given name is good */
969 if (name == NULL) {
970 TRAP_ERROR();
971 return (EINVAL);
972 }
973 if (ng_findhook(node, name) != NULL) {
974 TRAP_ERROR();
975 return (EEXIST);
976 }
977
978 /* Allocate the hook and link it up */
979 NG_ALLOC_HOOK(hook);
980 if (hook == NULL) {
981 TRAP_ERROR();
982 return (ENOMEM);
983 }
984 hook->hk_refs = 1; /* add a reference for us to return */
985 hook->hk_flags = HK_INVALID;
986 hook->hk_peer = &ng_deadhook; /* start off this way */
987 hook->hk_node = node;
988 NG_NODE_REF(node); /* each hook counts as a reference */
989
990 /* Set hook name */
991 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ);
992
993 /*
994 * Check if the node type code has something to say about it
995 * If it fails, the unref of the hook will also unref the node.
996 */
997 if (node->nd_type->newhook != NULL) {
998 if ((error = (*node->nd_type->newhook)(node, hook, name))) {
999 NG_HOOK_UNREF(hook); /* this frees the hook */
1000 return (error);
1001 }
1002 }
1003 /*
1004 * The 'type' agrees so far, so go ahead and link it in.
1005 * We'll ask again later when we actually connect the hooks.
1006 */
1007 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1008 node->nd_numhooks++;
1009 NG_HOOK_REF(hook); /* one for the node */
1010
1011 if (hookp)
1012 *hookp = hook;
1013 return (0);
1014 }
1015
1016 /*
1017 * Find a hook
1018 *
1019 * Node types may supply their own optimized routines for finding
1020 * hooks. If none is supplied, we just do a linear search.
1021 * XXX Possibly we should add a reference to the hook?
1022 */
1023 hook_p
1024 ng_findhook(node_p node, const char *name)
1025 {
1026 hook_p hook;
1027
1028 if (node->nd_type->findhook != NULL)
1029 return (*node->nd_type->findhook)(node, name);
1030 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
1031 if (NG_HOOK_IS_VALID(hook)
1032 && (strcmp(NG_HOOK_NAME(hook), name) == 0))
1033 return (hook);
1034 }
1035 return (NULL);
1036 }
1037
1038 /*
1039 * Destroy a hook
1040 *
1041 * As hooks are always attached, this really destroys two hooks.
1042 * The one given, and the one attached to it. Disconnect the hooks
1043 * from each other first. We reconnect the peer hook to the 'dead'
1044 * hook so that it can still exist after we depart. We then
1045 * send the peer its own destroy message. This ensures that we only
1046 * interact with the peer's structures when it is locked processing that
1047 * message. We hold a reference to the peer hook so we are guaranteed that
1048 * the peer hook and node are still going to exist until
1049 * we are finished there as the hook holds a ref on the node.
1050 * We run this same code again on the peer hook, but that time it is already
1051 * attached to the 'dead' hook.
1052 *
1053 * This routine is called at all stages of hook creation
1054 * on error detection and must be able to handle any such stage.
1055 */
1056 void
1057 ng_destroy_hook(hook_p hook)
1058 {
1059 hook_p peer;
1060 node_p node;
1061
1062 if (hook == &ng_deadhook) { /* better safe than sorry */
1063 printf("ng_destroy_hook called on deadhook\n");
1064 return;
1065 }
1066
1067 /*
1068 * Protect divorce process with mutex, to avoid races on
1069 * simultaneous disconnect.
1070 */
1071 mtx_lock(&ng_topo_mtx);
1072
1073 hook->hk_flags |= HK_INVALID;
1074
1075 peer = NG_HOOK_PEER(hook);
1076 node = NG_HOOK_NODE(hook);
1077
1078 if (peer && (peer != &ng_deadhook)) {
1079 /*
1080 * Set the peer to point to ng_deadhook
1081 * from this moment on we are effectively independent it.
1082 * send it an rmhook message of it's own.
1083 */
1084 peer->hk_peer = &ng_deadhook; /* They no longer know us */
1085 hook->hk_peer = &ng_deadhook; /* Nor us, them */
1086 if (NG_HOOK_NODE(peer) == &ng_deadnode) {
1087 /*
1088 * If it's already divorced from a node,
1089 * just free it.
1090 */
1091 mtx_unlock(&ng_topo_mtx);
1092 } else {
1093 mtx_unlock(&ng_topo_mtx);
1094 ng_rmhook_self(peer); /* Send it a surprise */
1095 }
1096 NG_HOOK_UNREF(peer); /* account for peer link */
1097 NG_HOOK_UNREF(hook); /* account for peer link */
1098 } else
1099 mtx_unlock(&ng_topo_mtx);
1100
1101 mtx_assert(&ng_topo_mtx, MA_NOTOWNED);
1102
1103 /*
1104 * Remove the hook from the node's list to avoid possible recursion
1105 * in case the disconnection results in node shutdown.
1106 */
1107 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */
1108 return;
1109 }
1110 LIST_REMOVE(hook, hk_hooks);
1111 node->nd_numhooks--;
1112 if (node->nd_type->disconnect) {
1113 /*
1114 * The type handler may elect to destroy the node so don't
1115 * trust its existence after this point. (except
1116 * that we still hold a reference on it. (which we
1117 * inherrited from the hook we are destroying)
1118 */
1119 (*node->nd_type->disconnect) (hook);
1120 }
1121
1122 /*
1123 * Note that because we will point to ng_deadnode, the original node
1124 * is not decremented automatically so we do that manually.
1125 */
1126 _NG_HOOK_NODE(hook) = &ng_deadnode;
1127 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */
1128 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */
1129 }
1130
1131 /*
1132 * Take two hooks on a node and merge the connection so that the given node
1133 * is effectively bypassed.
1134 */
1135 int
1136 ng_bypass(hook_p hook1, hook_p hook2)
1137 {
1138 if (hook1->hk_node != hook2->hk_node) {
1139 TRAP_ERROR();
1140 return (EINVAL);
1141 }
1142 hook1->hk_peer->hk_peer = hook2->hk_peer;
1143 hook2->hk_peer->hk_peer = hook1->hk_peer;
1144
1145 hook1->hk_peer = &ng_deadhook;
1146 hook2->hk_peer = &ng_deadhook;
1147
1148 NG_HOOK_UNREF(hook1);
1149 NG_HOOK_UNREF(hook2);
1150
1151 /* XXX If we ever cache methods on hooks update them as well */
1152 ng_destroy_hook(hook1);
1153 ng_destroy_hook(hook2);
1154 return (0);
1155 }
1156
1157 /*
1158 * Install a new netgraph type
1159 */
1160 int
1161 ng_newtype(struct ng_type *tp)
1162 {
1163 const size_t namelen = strlen(tp->name);
1164
1165 /* Check version and type name fields */
1166 if ((tp->version != NG_ABI_VERSION)
1167 || (namelen == 0)
1168 || (namelen >= NG_TYPESIZ)) {
1169 TRAP_ERROR();
1170 if (tp->version != NG_ABI_VERSION) {
1171 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n");
1172 }
1173 return (EINVAL);
1174 }
1175
1176 /* Check for name collision */
1177 if (ng_findtype(tp->name) != NULL) {
1178 TRAP_ERROR();
1179 return (EEXIST);
1180 }
1181
1182
1183 /* Link in new type */
1184 mtx_lock(&ng_typelist_mtx);
1185 LIST_INSERT_HEAD(&ng_typelist, tp, types);
1186 tp->refs = 1; /* first ref is linked list */
1187 mtx_unlock(&ng_typelist_mtx);
1188 return (0);
1189 }
1190
1191 /*
1192 * unlink a netgraph type
1193 * If no examples exist
1194 */
1195 int
1196 ng_rmtype(struct ng_type *tp)
1197 {
1198 /* Check for name collision */
1199 if (tp->refs != 1) {
1200 TRAP_ERROR();
1201 return (EBUSY);
1202 }
1203
1204 /* Unlink type */
1205 mtx_lock(&ng_typelist_mtx);
1206 LIST_REMOVE(tp, types);
1207 mtx_unlock(&ng_typelist_mtx);
1208 return (0);
1209 }
1210
1211 /*
1212 * Look for a type of the name given
1213 */
1214 struct ng_type *
1215 ng_findtype(const char *typename)
1216 {
1217 struct ng_type *type;
1218
1219 mtx_lock(&ng_typelist_mtx);
1220 LIST_FOREACH(type, &ng_typelist, types) {
1221 if (strcmp(type->name, typename) == 0)
1222 break;
1223 }
1224 mtx_unlock(&ng_typelist_mtx);
1225 return (type);
1226 }
1227
1228 /************************************************************************
1229 Composite routines
1230 ************************************************************************/
1231 /*
1232 * Connect two nodes using the specified hooks, using queued functions.
1233 */
1234 static int
1235 ng_con_part3(node_p node, item_p item, hook_p hook)
1236 {
1237 int error = 0;
1238
1239 /*
1240 * When we run, we know that the node 'node' is locked for us.
1241 * Our caller has a reference on the hook.
1242 * Our caller has a reference on the node.
1243 * (In this case our caller is ng_apply_item() ).
1244 * The peer hook has a reference on the hook.
1245 * We are all set up except for the final call to the node, and
1246 * the clearing of the INVALID flag.
1247 */
1248 if (NG_HOOK_NODE(hook) == &ng_deadnode) {
1249 /*
1250 * The node must have been freed again since we last visited
1251 * here. ng_destry_hook() has this effect but nothing else does.
1252 * We should just release our references and
1253 * free anything we can think of.
1254 * Since we know it's been destroyed, and it's our caller
1255 * that holds the references, just return.
1256 */
1257 ERROUT(ENOENT);
1258 }
1259 if (hook->hk_node->nd_type->connect) {
1260 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1261 ng_destroy_hook(hook); /* also zaps peer */
1262 printf("failed in ng_con_part3()\n");
1263 ERROUT(error);
1264 }
1265 }
1266 /*
1267 * XXX this is wrong for SMP. Possibly we need
1268 * to separate out 'create' and 'invalid' flags.
1269 * should only set flags on hooks we have locked under our node.
1270 */
1271 hook->hk_flags &= ~HK_INVALID;
1272 done:
1273 NG_FREE_ITEM(item);
1274 return (error);
1275 }
1276
1277 static int
1278 ng_con_part2(node_p node, item_p item, hook_p hook)
1279 {
1280 hook_p peer;
1281 int error = 0;
1282
1283 /*
1284 * When we run, we know that the node 'node' is locked for us.
1285 * Our caller has a reference on the hook.
1286 * Our caller has a reference on the node.
1287 * (In this case our caller is ng_apply_item() ).
1288 * The peer hook has a reference on the hook.
1289 * our node pointer points to the 'dead' node.
1290 * First check the hook name is unique.
1291 * Should not happen because we checked before queueing this.
1292 */
1293 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) {
1294 TRAP_ERROR();
1295 ng_destroy_hook(hook); /* should destroy peer too */
1296 printf("failed in ng_con_part2()\n");
1297 ERROUT(EEXIST);
1298 }
1299 /*
1300 * Check if the node type code has something to say about it
1301 * If it fails, the unref of the hook will also unref the attached node,
1302 * however since that node is 'ng_deadnode' this will do nothing.
1303 * The peer hook will also be destroyed.
1304 */
1305 if (node->nd_type->newhook != NULL) {
1306 if ((error = (*node->nd_type->newhook)(node, hook,
1307 hook->hk_name))) {
1308 ng_destroy_hook(hook); /* should destroy peer too */
1309 printf("failed in ng_con_part2()\n");
1310 ERROUT(error);
1311 }
1312 }
1313
1314 /*
1315 * The 'type' agrees so far, so go ahead and link it in.
1316 * We'll ask again later when we actually connect the hooks.
1317 */
1318 hook->hk_node = node; /* just overwrite ng_deadnode */
1319 NG_NODE_REF(node); /* each hook counts as a reference */
1320 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1321 node->nd_numhooks++;
1322 NG_HOOK_REF(hook); /* one for the node */
1323
1324 /*
1325 * We now have a symmetrical situation, where both hooks have been
1326 * linked to their nodes, the newhook methods have been called
1327 * And the references are all correct. The hooks are still marked
1328 * as invalid, as we have not called the 'connect' methods
1329 * yet.
1330 * We can call the local one immediately as we have the
1331 * node locked, but we need to queue the remote one.
1332 */
1333 if (hook->hk_node->nd_type->connect) {
1334 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1335 ng_destroy_hook(hook); /* also zaps peer */
1336 printf("failed in ng_con_part2(A)\n");
1337 ERROUT(error);
1338 }
1339 }
1340
1341 /*
1342 * Acquire topo mutex to avoid race with ng_destroy_hook().
1343 */
1344 mtx_lock(&ng_topo_mtx);
1345 peer = hook->hk_peer;
1346 if (peer == &ng_deadhook) {
1347 mtx_unlock(&ng_topo_mtx);
1348 printf("failed in ng_con_part2(B)\n");
1349 ng_destroy_hook(hook);
1350 ERROUT(ENOENT);
1351 }
1352 mtx_unlock(&ng_topo_mtx);
1353
1354 if ((error = ng_send_fn2(peer->hk_node, peer, item, &ng_con_part3,
1355 NULL, 0, NG_REUSE_ITEM))) {
1356 printf("failed in ng_con_part2(C)\n");
1357 ng_destroy_hook(hook); /* also zaps peer */
1358 return (error); /* item was consumed. */
1359 }
1360 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */
1361 return (0); /* item was consumed. */
1362 done:
1363 NG_FREE_ITEM(item);
1364 return (error);
1365 }
1366
1367 /*
1368 * Connect this node with another node. We assume that this node is
1369 * currently locked, as we are only called from an NGM_CONNECT message.
1370 */
1371 static int
1372 ng_con_nodes(item_p item, node_p node, const char *name,
1373 node_p node2, const char *name2)
1374 {
1375 int error;
1376 hook_p hook;
1377 hook_p hook2;
1378
1379 if (ng_findhook(node2, name2) != NULL) {
1380 return(EEXIST);
1381 }
1382 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */
1383 return (error);
1384 /* Allocate the other hook and link it up */
1385 NG_ALLOC_HOOK(hook2);
1386 if (hook2 == NULL) {
1387 TRAP_ERROR();
1388 ng_destroy_hook(hook); /* XXX check ref counts so far */
1389 NG_HOOK_UNREF(hook); /* including our ref */
1390 return (ENOMEM);
1391 }
1392 hook2->hk_refs = 1; /* start with a reference for us. */
1393 hook2->hk_flags = HK_INVALID;
1394 hook2->hk_peer = hook; /* Link the two together */
1395 hook->hk_peer = hook2;
1396 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/
1397 NG_HOOK_REF(hook2);
1398 hook2->hk_node = &ng_deadnode;
1399 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ);
1400
1401 /*
1402 * Queue the function above.
1403 * Procesing continues in that function in the lock context of
1404 * the other node.
1405 */
1406 if ((error = ng_send_fn2(node2, hook2, item, &ng_con_part2, NULL, 0,
1407 NG_NOFLAGS))) {
1408 printf("failed in ng_con_nodes(): %d\n", error);
1409 ng_destroy_hook(hook); /* also zaps peer */
1410 }
1411
1412 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */
1413 NG_HOOK_UNREF(hook2);
1414 return (error);
1415 }
1416
1417 /*
1418 * Make a peer and connect.
1419 * We assume that the local node is locked.
1420 * The new node probably doesn't need a lock until
1421 * it has a hook, because it cannot really have any work until then,
1422 * but we should think about it a bit more.
1423 *
1424 * The problem may come if the other node also fires up
1425 * some hardware or a timer or some other source of activation,
1426 * also it may already get a command msg via it's ID.
1427 *
1428 * We could use the same method as ng_con_nodes() but we'd have
1429 * to add ability to remove the node when failing. (Not hard, just
1430 * make arg1 point to the node to remove).
1431 * Unless of course we just ignore failure to connect and leave
1432 * an unconnected node?
1433 */
1434 static int
1435 ng_mkpeer(node_p node, const char *name, const char *name2, char *type)
1436 {
1437 node_p node2;
1438 hook_p hook1, hook2;
1439 int error;
1440
1441 if ((error = ng_make_node(type, &node2))) {
1442 return (error);
1443 }
1444
1445 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */
1446 ng_rmnode(node2, NULL, NULL, 0);
1447 return (error);
1448 }
1449
1450 if ((error = ng_add_hook(node2, name2, &hook2))) {
1451 ng_rmnode(node2, NULL, NULL, 0);
1452 ng_destroy_hook(hook1);
1453 NG_HOOK_UNREF(hook1);
1454 return (error);
1455 }
1456
1457 /*
1458 * Actually link the two hooks together.
1459 */
1460 hook1->hk_peer = hook2;
1461 hook2->hk_peer = hook1;
1462
1463 /* Each hook is referenced by the other */
1464 NG_HOOK_REF(hook1);
1465 NG_HOOK_REF(hook2);
1466
1467 /* Give each node the opportunity to veto the pending connection */
1468 if (hook1->hk_node->nd_type->connect) {
1469 error = (*hook1->hk_node->nd_type->connect) (hook1);
1470 }
1471
1472 if ((error == 0) && hook2->hk_node->nd_type->connect) {
1473 error = (*hook2->hk_node->nd_type->connect) (hook2);
1474
1475 }
1476
1477 /*
1478 * drop the references we were holding on the two hooks.
1479 */
1480 if (error) {
1481 ng_destroy_hook(hook2); /* also zaps hook1 */
1482 ng_rmnode(node2, NULL, NULL, 0);
1483 } else {
1484 /* As a last act, allow the hooks to be used */
1485 hook1->hk_flags &= ~HK_INVALID;
1486 hook2->hk_flags &= ~HK_INVALID;
1487 }
1488 NG_HOOK_UNREF(hook1);
1489 NG_HOOK_UNREF(hook2);
1490 return (error);
1491 }
1492
1493 /************************************************************************
1494 Utility routines to send self messages
1495 ************************************************************************/
1496
1497 /* Shut this node down as soon as everyone is clear of it */
1498 /* Should add arg "immediately" to jump the queue */
1499 int
1500 ng_rmnode_self(node_p node)
1501 {
1502 int error;
1503
1504 if (node == &ng_deadnode)
1505 return (0);
1506 node->nd_flags |= NGF_INVALID;
1507 if (node->nd_flags & NGF_CLOSING)
1508 return (0);
1509
1510 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0);
1511 return (error);
1512 }
1513
1514 static void
1515 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2)
1516 {
1517 ng_destroy_hook(hook);
1518 return ;
1519 }
1520
1521 int
1522 ng_rmhook_self(hook_p hook)
1523 {
1524 int error;
1525 node_p node = NG_HOOK_NODE(hook);
1526
1527 if (node == &ng_deadnode)
1528 return (0);
1529
1530 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0);
1531 return (error);
1532 }
1533
1534 /***********************************************************************
1535 * Parse and verify a string of the form: <NODE:><PATH>
1536 *
1537 * Such a string can refer to a specific node or a specific hook
1538 * on a specific node, depending on how you look at it. In the
1539 * latter case, the PATH component must not end in a dot.
1540 *
1541 * Both <NODE:> and <PATH> are optional. The <PATH> is a string
1542 * of hook names separated by dots. This breaks out the original
1543 * string, setting *nodep to "NODE" (or NULL if none) and *pathp
1544 * to "PATH" (or NULL if degenerate). Also, *hookp will point to
1545 * the final hook component of <PATH>, if any, otherwise NULL.
1546 *
1547 * This returns -1 if the path is malformed. The char ** are optional.
1548 ***********************************************************************/
1549 int
1550 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp)
1551 {
1552 char *node, *path, *hook;
1553 int k;
1554
1555 /*
1556 * Extract absolute NODE, if any
1557 */
1558 for (path = addr; *path && *path != ':'; path++);
1559 if (*path) {
1560 node = addr; /* Here's the NODE */
1561 *path++ = '\0'; /* Here's the PATH */
1562
1563 /* Node name must not be empty */
1564 if (!*node)
1565 return -1;
1566
1567 /* A name of "." is OK; otherwise '.' not allowed */
1568 if (strcmp(node, ".") != 0) {
1569 for (k = 0; node[k]; k++)
1570 if (node[k] == '.')
1571 return -1;
1572 }
1573 } else {
1574 node = NULL; /* No absolute NODE */
1575 path = addr; /* Here's the PATH */
1576 }
1577
1578 /* Snoop for illegal characters in PATH */
1579 for (k = 0; path[k]; k++)
1580 if (path[k] == ':')
1581 return -1;
1582
1583 /* Check for no repeated dots in PATH */
1584 for (k = 0; path[k]; k++)
1585 if (path[k] == '.' && path[k + 1] == '.')
1586 return -1;
1587
1588 /* Remove extra (degenerate) dots from beginning or end of PATH */
1589 if (path[0] == '.')
1590 path++;
1591 if (*path && path[strlen(path) - 1] == '.')
1592 path[strlen(path) - 1] = 0;
1593
1594 /* If PATH has a dot, then we're not talking about a hook */
1595 if (*path) {
1596 for (hook = path, k = 0; path[k]; k++)
1597 if (path[k] == '.') {
1598 hook = NULL;
1599 break;
1600 }
1601 } else
1602 path = hook = NULL;
1603
1604 /* Done */
1605 if (nodep)
1606 *nodep = node;
1607 if (pathp)
1608 *pathp = path;
1609 if (hookp)
1610 *hookp = hook;
1611 return (0);
1612 }
1613
1614 /*
1615 * Given a path, which may be absolute or relative, and a starting node,
1616 * return the destination node.
1617 */
1618 int
1619 ng_path2noderef(node_p here, const char *address,
1620 node_p *destp, hook_p *lasthook)
1621 {
1622 char fullpath[NG_PATHSIZ];
1623 char *nodename, *path, pbuf[2];
1624 node_p node, oldnode;
1625 char *cp;
1626 hook_p hook = NULL;
1627
1628 /* Initialize */
1629 if (destp == NULL) {
1630 TRAP_ERROR();
1631 return EINVAL;
1632 }
1633 *destp = NULL;
1634
1635 /* Make a writable copy of address for ng_path_parse() */
1636 strncpy(fullpath, address, sizeof(fullpath) - 1);
1637 fullpath[sizeof(fullpath) - 1] = '\0';
1638
1639 /* Parse out node and sequence of hooks */
1640 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) {
1641 TRAP_ERROR();
1642 return EINVAL;
1643 }
1644 if (path == NULL) {
1645 pbuf[0] = '.'; /* Needs to be writable */
1646 pbuf[1] = '\0';
1647 path = pbuf;
1648 }
1649
1650 /*
1651 * For an absolute address, jump to the starting node.
1652 * Note that this holds a reference on the node for us.
1653 * Don't forget to drop the reference if we don't need it.
1654 */
1655 if (nodename) {
1656 node = ng_name2noderef(here, nodename);
1657 if (node == NULL) {
1658 TRAP_ERROR();
1659 return (ENOENT);
1660 }
1661 } else {
1662 if (here == NULL) {
1663 TRAP_ERROR();
1664 return (EINVAL);
1665 }
1666 node = here;
1667 NG_NODE_REF(node);
1668 }
1669
1670 /*
1671 * Now follow the sequence of hooks
1672 * XXX
1673 * We actually cannot guarantee that the sequence
1674 * is not being demolished as we crawl along it
1675 * without extra-ordinary locking etc.
1676 * So this is a bit dodgy to say the least.
1677 * We can probably hold up some things by holding
1678 * the nodelist mutex for the time of this
1679 * crawl if we wanted.. At least that way we wouldn't have to
1680 * worry about the nodes disappearing, but the hooks would still
1681 * be a problem.
1682 */
1683 for (cp = path; node != NULL && *cp != '\0'; ) {
1684 char *segment;
1685
1686 /*
1687 * Break out the next path segment. Replace the dot we just
1688 * found with a NUL; "cp" points to the next segment (or the
1689 * NUL at the end).
1690 */
1691 for (segment = cp; *cp != '\0'; cp++) {
1692 if (*cp == '.') {
1693 *cp++ = '\0';
1694 break;
1695 }
1696 }
1697
1698 /* Empty segment */
1699 if (*segment == '\0')
1700 continue;
1701
1702 /* We have a segment, so look for a hook by that name */
1703 hook = ng_findhook(node, segment);
1704
1705 /* Can't get there from here... */
1706 if (hook == NULL
1707 || NG_HOOK_PEER(hook) == NULL
1708 || NG_HOOK_NOT_VALID(hook)
1709 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) {
1710 TRAP_ERROR();
1711 NG_NODE_UNREF(node);
1712 #if 0
1713 printf("hooknotvalid %s %s %d %d %d %d ",
1714 path,
1715 segment,
1716 hook == NULL,
1717 NG_HOOK_PEER(hook) == NULL,
1718 NG_HOOK_NOT_VALID(hook),
1719 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)));
1720 #endif
1721 return (ENOENT);
1722 }
1723
1724 /*
1725 * Hop on over to the next node
1726 * XXX
1727 * Big race conditions here as hooks and nodes go away
1728 * *** Idea.. store an ng_ID_t in each hook and use that
1729 * instead of the direct hook in this crawl?
1730 */
1731 oldnode = node;
1732 if ((node = NG_PEER_NODE(hook)))
1733 NG_NODE_REF(node); /* XXX RACE */
1734 NG_NODE_UNREF(oldnode); /* XXX another race */
1735 if (NG_NODE_NOT_VALID(node)) {
1736 NG_NODE_UNREF(node); /* XXX more races */
1737 node = NULL;
1738 }
1739 }
1740
1741 /* If node somehow missing, fail here (probably this is not needed) */
1742 if (node == NULL) {
1743 TRAP_ERROR();
1744 return (ENXIO);
1745 }
1746
1747 /* Done */
1748 *destp = node;
1749 if (lasthook != NULL)
1750 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL);
1751 return (0);
1752 }
1753
1754 /***************************************************************\
1755 * Input queue handling.
1756 * All activities are submitted to the node via the input queue
1757 * which implements a multiple-reader/single-writer gate.
1758 * Items which cannot be handled immediately are queued.
1759 *
1760 * read-write queue locking inline functions *
1761 \***************************************************************/
1762
1763 static __inline item_p ng_dequeue(struct ng_queue * ngq, int *rw);
1764 static __inline item_p ng_acquire_read(struct ng_queue * ngq,
1765 item_p item);
1766 static __inline item_p ng_acquire_write(struct ng_queue * ngq,
1767 item_p item);
1768 static __inline void ng_leave_read(struct ng_queue * ngq);
1769 static __inline void ng_leave_write(struct ng_queue * ngq);
1770 static __inline void ng_queue_rw(struct ng_queue * ngq,
1771 item_p item, int rw);
1772
1773 /*
1774 * Definition of the bits fields in the ng_queue flag word.
1775 * Defined here rather than in netgraph.h because no-one should fiddle
1776 * with them.
1777 *
1778 * The ordering here may be important! don't shuffle these.
1779 */
1780 /*-
1781 Safety Barrier--------+ (adjustable to suit taste) (not used yet)
1782 |
1783 V
1784 +-------+-------+-------+-------+-------+-------+-------+-------+
1785 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
1786 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A|
1787 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W|
1788 +-------+-------+-------+-------+-------+-------+-------+-------+
1789 \___________________________ ____________________________/ | |
1790 V | |
1791 [active reader count] | |
1792 | |
1793 Operation Pending -------------------------------+ |
1794 |
1795 Active Writer ---------------------------------------+
1796
1797
1798 */
1799 #define WRITER_ACTIVE 0x00000001
1800 #define OP_PENDING 0x00000002
1801 #define READER_INCREMENT 0x00000004
1802 #define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */
1803 #define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */
1804
1805 /* Defines of more elaborate states on the queue */
1806 /* Mask of bits a new read cares about */
1807 #define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING)
1808
1809 /* Mask of bits a new write cares about */
1810 #define NGQ_WMASK (NGQ_RMASK|READER_MASK)
1811
1812 /* Test to decide if there is something on the queue. */
1813 #define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING)
1814
1815 /* How to decide what the next queued item is. */
1816 #define HEAD_IS_READER(QP) NGI_QUEUED_READER((QP)->queue)
1817 #define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER((QP)->queue) /* notused */
1818
1819 /* Read the status to decide if the next item on the queue can now run. */
1820 #define QUEUED_READER_CAN_PROCEED(QP) \
1821 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0)
1822 #define QUEUED_WRITER_CAN_PROCEED(QP) \
1823 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0)
1824
1825 /* Is there a chance of getting ANY work off the queue? */
1826 #define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \
1827 (QUEUE_ACTIVE(QP) && \
1828 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \
1829 QUEUED_WRITER_CAN_PROCEED(QP)))
1830
1831
1832 #define NGQRW_R 0
1833 #define NGQRW_W 1
1834
1835 /*
1836 * Taking into account the current state of the queue and node, possibly take
1837 * the next entry off the queue and return it. Return NULL if there was
1838 * nothing we could return, either because there really was nothing there, or
1839 * because the node was in a state where it cannot yet process the next item
1840 * on the queue.
1841 *
1842 * This MUST MUST MUST be called with the mutex held.
1843 */
1844 static __inline item_p
1845 ng_dequeue(struct ng_queue *ngq, int *rw)
1846 {
1847 item_p item;
1848 u_int add_arg;
1849
1850 mtx_assert(&ngq->q_mtx, MA_OWNED);
1851 /*
1852 * If there is nothing queued, then just return.
1853 * No point in continuing.
1854 * XXXGL: assert this?
1855 */
1856 if (!QUEUE_ACTIVE(ngq)) {
1857 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; "
1858 "queue flags 0x%lx", __func__,
1859 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags);
1860 return (NULL);
1861 }
1862
1863 /*
1864 * From here, we can assume there is a head item.
1865 * We need to find out what it is and if it can be dequeued, given
1866 * the current state of the node.
1867 */
1868 if (HEAD_IS_READER(ngq)) {
1869 if (!QUEUED_READER_CAN_PROCEED(ngq)) {
1870 /*
1871 * It's a reader but we can't use it.
1872 * We are stalled so make sure we don't
1873 * get called again until something changes.
1874 */
1875 ng_worklist_remove(ngq->q_node);
1876 CTR4(KTR_NET, "%20s: node [%x] (%p) queued reader "
1877 "can't proceed; queue flags 0x%lx", __func__,
1878 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags);
1879 return (NULL);
1880 }
1881 /*
1882 * Head of queue is a reader and we have no write active.
1883 * We don't care how many readers are already active.
1884 * Add the correct increment for the reader count.
1885 */
1886 add_arg = READER_INCREMENT;
1887 *rw = NGQRW_R;
1888 } else if (QUEUED_WRITER_CAN_PROCEED(ngq)) {
1889 /*
1890 * There is a pending write, no readers and no active writer.
1891 * This means we can go ahead with the pending writer. Note
1892 * the fact that we now have a writer, ready for when we take
1893 * it off the queue.
1894 *
1895 * We don't need to worry about a possible collision with the
1896 * fasttrack reader.
1897 *
1898 * The fasttrack thread may take a long time to discover that we
1899 * are running so we would have an inconsistent state in the
1900 * flags for a while. Since we ignore the reader count
1901 * entirely when the WRITER_ACTIVE flag is set, this should
1902 * not matter (in fact it is defined that way). If it tests
1903 * the flag before this operation, the OP_PENDING flag
1904 * will make it fail, and if it tests it later, the
1905 * WRITER_ACTIVE flag will do the same. If it is SO slow that
1906 * we have actually completed the operation, and neither flag
1907 * is set by the time that it tests the flags, then it is
1908 * actually ok for it to continue. If it completes and we've
1909 * finished and the read pending is set it still fails.
1910 *
1911 * So we can just ignore it, as long as we can ensure that the
1912 * transition from WRITE_PENDING state to the WRITER_ACTIVE
1913 * state is atomic.
1914 *
1915 * After failing, first it will be held back by the mutex, then
1916 * when it can proceed, it will queue its request, then it
1917 * would arrive at this function. Usually it will have to
1918 * leave empty handed because the ACTIVE WRITER bit will be
1919 * set.
1920 *
1921 * Adjust the flags for the new active writer.
1922 */
1923 add_arg = WRITER_ACTIVE;
1924 *rw = NGQRW_W;
1925 /*
1926 * We want to write "active writer, no readers " Now go make
1927 * it true. In fact there may be a number in the readers
1928 * count but we know it is not true and will be fixed soon.
1929 * We will fix the flags for the next pending entry in a
1930 * moment.
1931 */
1932 } else {
1933 /*
1934 * We can't dequeue anything.. return and say so. Probably we
1935 * have a write pending and the readers count is non zero. If
1936 * we got here because a reader hit us just at the wrong
1937 * moment with the fasttrack code, and put us in a strange
1938 * state, then it will be coming through in just a moment,
1939 * (just as soon as we release the mutex) and keep things
1940 * moving.
1941 * Make sure we remove ourselves from the work queue. It
1942 * would be a waste of effort to do all this again.
1943 */
1944 ng_worklist_remove(ngq->q_node);
1945 CTR4(KTR_NET, "%20s: node [%x] (%p) can't dequeue anything; "
1946 "queue flags 0x%lx", __func__,
1947 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags);
1948 return (NULL);
1949 }
1950
1951 /*
1952 * Now we dequeue the request (whatever it may be) and correct the
1953 * pending flags and the next and last pointers.
1954 */
1955 item = ngq->queue;
1956 ngq->queue = item->el_next;
1957 CTR6(KTR_NET, "%20s: node [%x] (%p) dequeued item %p with flags 0x%lx; "
1958 "queue flags 0x%lx", __func__,
1959 ngq->q_node->nd_ID,ngq->q_node, item, item->el_flags, ngq->q_flags);
1960 if (ngq->last == &(item->el_next)) {
1961 /*
1962 * that was the last entry in the queue so set the 'last
1963 * pointer up correctly and make sure the pending flag is
1964 * clear.
1965 */
1966 add_arg += -OP_PENDING;
1967 ngq->last = &(ngq->queue);
1968 /*
1969 * Whatever flag was set will be cleared and
1970 * the new acive field will be set by the add as well,
1971 * so we don't need to change add_arg.
1972 * But we know we don't need to be on the work list.
1973 */
1974 atomic_add_long(&ngq->q_flags, add_arg);
1975 ng_worklist_remove(ngq->q_node);
1976 } else {
1977 /*
1978 * Since there is still something on the queue
1979 * we don't need to change the PENDING flag.
1980 */
1981 atomic_add_long(&ngq->q_flags, add_arg);
1982 /*
1983 * If we see more doable work, make sure we are
1984 * on the work queue.
1985 */
1986 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) {
1987 ng_setisr(ngq->q_node);
1988 }
1989 }
1990 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; "
1991 "queue flags 0x%lx", __func__,
1992 ngq->q_node->nd_ID, ngq->q_node, item, *rw ? "WRITER" : "READER" ,
1993 ngq->q_flags);
1994 return (item);
1995 }
1996
1997 /*
1998 * Queue a packet to be picked up by someone else.
1999 * We really don't care who, but we can't or don't want to hang around
2000 * to process it ourselves. We are probably an interrupt routine..
2001 * If the queue could be run, flag the netisr handler to start.
2002 */
2003 static __inline void
2004 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw)
2005 {
2006 mtx_assert(&ngq->q_mtx, MA_OWNED);
2007
2008 if (rw == NGQRW_W)
2009 NGI_SET_WRITER(item);
2010 else
2011 NGI_SET_READER(item);
2012 item->el_next = NULL; /* maybe not needed */
2013 *ngq->last = item;
2014 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__,
2015 ngq->q_node->nd_ID, ngq->q_node, item, rw ? "WRITER" : "READER" );
2016 /*
2017 * If it was the first item in the queue then we need to
2018 * set the last pointer and the type flags.
2019 */
2020 if (ngq->last == &(ngq->queue)) {
2021 atomic_add_long(&ngq->q_flags, OP_PENDING);
2022 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__,
2023 ngq->q_node->nd_ID, ngq->q_node);
2024 }
2025
2026 ngq->last = &(item->el_next);
2027 /*
2028 * We can take the worklist lock with the node locked
2029 * BUT NOT THE REVERSE!
2030 */
2031 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2032 ng_setisr(ngq->q_node);
2033 }
2034
2035
2036 /*
2037 * This function 'cheats' in that it first tries to 'grab' the use of the
2038 * node, without going through the mutex. We can do this becasue of the
2039 * semantics of the lock. The semantics include a clause that says that the
2040 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It
2041 * also says that the WRITER_ACTIVE flag cannot be set if the readers count
2042 * is not zero. Note that this talks about what is valid to SET the
2043 * WRITER_ACTIVE flag, because from the moment it is set, the value if the
2044 * reader count is immaterial, and not valid. The two 'pending' flags have a
2045 * similar effect, in that If they are orthogonal to the two active fields in
2046 * how they are set, but if either is set, the attempted 'grab' need to be
2047 * backed out because there is earlier work, and we maintain ordering in the
2048 * queue. The result of this is that the reader request can try obtain use of
2049 * the node with only a single atomic addition, and without any of the mutex
2050 * overhead. If this fails the operation degenerates to the same as for other
2051 * cases.
2052 *
2053 */
2054 static __inline item_p
2055 ng_acquire_read(struct ng_queue *ngq, item_p item)
2056 {
2057 KASSERT(ngq != &ng_deadnode.nd_input_queue,
2058 ("%s: working on deadnode", __func__));
2059
2060 /* ######### Hack alert ######### */
2061 atomic_add_long(&ngq->q_flags, READER_INCREMENT);
2062 if ((ngq->q_flags & NGQ_RMASK) == 0) {
2063 /* Successfully grabbed node */
2064 CTR4(KTR_NET, "%20s: node [%x] (%p) fast acquired item %p",
2065 __func__, ngq->q_node->nd_ID, ngq->q_node, item);
2066 return (item);
2067 }
2068 /* undo the damage if we didn't succeed */
2069 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT);
2070
2071 /* ######### End Hack alert ######### */
2072 NG_QUEUE_LOCK(ngq);
2073 /*
2074 * Try again. Another processor (or interrupt for that matter) may
2075 * have removed the last queued item that was stopping us from
2076 * running, between the previous test, and the moment that we took
2077 * the mutex. (Or maybe a writer completed.)
2078 * Even if another fast-track reader hits during this period
2079 * we don't care as multiple readers is OK.
2080 */
2081 if ((ngq->q_flags & NGQ_RMASK) == 0) {
2082 atomic_add_long(&ngq->q_flags, READER_INCREMENT);
2083 NG_QUEUE_UNLOCK(ngq);
2084 CTR4(KTR_NET, "%20s: node [%x] (%p) slow acquired item %p",
2085 __func__, ngq->q_node->nd_ID, ngq->q_node, item);
2086 return (item);
2087 }
2088
2089 /*
2090 * and queue the request for later.
2091 */
2092 ng_queue_rw(ngq, item, NGQRW_R);
2093 NG_QUEUE_UNLOCK(ngq);
2094
2095 return (NULL);
2096 }
2097
2098 static __inline item_p
2099 ng_acquire_write(struct ng_queue *ngq, item_p item)
2100 {
2101 KASSERT(ngq != &ng_deadnode.nd_input_queue,
2102 ("%s: working on deadnode", __func__));
2103
2104 restart:
2105 NG_QUEUE_LOCK(ngq);
2106 /*
2107 * If there are no readers, no writer, and no pending packets, then
2108 * we can just go ahead. In all other situations we need to queue the
2109 * request
2110 */
2111 if ((ngq->q_flags & NGQ_WMASK) == 0) {
2112 /* collision could happen *HERE* */
2113 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE);
2114 NG_QUEUE_UNLOCK(ngq);
2115 if (ngq->q_flags & READER_MASK) {
2116 /* Collision with fast-track reader */
2117 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE);
2118 goto restart;
2119 }
2120 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
2121 __func__, ngq->q_node->nd_ID, ngq->q_node, item);
2122 return (item);
2123 }
2124
2125 /*
2126 * and queue the request for later.
2127 */
2128 ng_queue_rw(ngq, item, NGQRW_W);
2129 NG_QUEUE_UNLOCK(ngq);
2130
2131 return (NULL);
2132 }
2133
2134 #if 0
2135 static __inline item_p
2136 ng_upgrade_write(struct ng_queue *ngq, item_p item)
2137 {
2138 KASSERT(ngq != &ng_deadnode.nd_input_queue,
2139 ("%s: working on deadnode", __func__));
2140
2141 NGI_SET_WRITER(item);
2142
2143 mtx_lock_spin(&(ngq->q_mtx));
2144
2145 /*
2146 * There will never be no readers as we are there ourselves.
2147 * Set the WRITER_ACTIVE flags ASAP to block out fast track readers.
2148 * The caller we are running from will call ng_leave_read()
2149 * soon, so we must account for that. We must leave again with the
2150 * READER lock. If we find other readers, then
2151 * queue the request for later. However "later" may be rignt now
2152 * if there are no readers. We don't really care if there are queued
2153 * items as we will bypass them anyhow.
2154 */
2155 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT);
2156 if (ngq->q_flags & (NGQ_WMASK & ~OP_PENDING) == WRITER_ACTIVE) {
2157 mtx_unlock_spin(&(ngq->q_mtx));
2158
2159 /* It's just us, act on the item. */
2160 /* will NOT drop writer lock when done */
2161 ng_apply_item(node, item, 0);
2162
2163 /*
2164 * Having acted on the item, atomically
2165 * down grade back to READER and finish up
2166 */
2167 atomic_add_long(&ngq->q_flags,
2168 READER_INCREMENT - WRITER_ACTIVE);
2169
2170 /* Our caller will call ng_leave_read() */
2171 return;
2172 }
2173 /*
2174 * It's not just us active, so queue us AT THE HEAD.
2175 * "Why?" I hear you ask.
2176 * Put us at the head of the queue as we've already been
2177 * through it once. If there is nothing else waiting,
2178 * set the correct flags.
2179 */
2180 if ((item->el_next = ngq->queue) == NULL) {
2181 /*
2182 * Set up the "last" pointer.
2183 * We are the only (and thus last) item
2184 */
2185 ngq->last = &(item->el_next);
2186
2187 /* We've gone from, 0 to 1 item in the queue */
2188 atomic_add_long(&ngq->q_flags, OP_PENDING);
2189
2190 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__,
2191 ngq->q_node->nd_ID, ngq->q_node);
2192 };
2193 ngq->queue = item;
2194 CTR5(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER",
2195 __func__, ngq->q_node->nd_ID, ngq->q_node, item );
2196
2197 /* Reverse what we did above. That downgrades us back to reader */
2198 atomic_add_long(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE);
2199 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2200 ng_setisr(ngq->q_node);
2201 mtx_unlock_spin(&(ngq->q_mtx));
2202
2203 return;
2204 }
2205
2206 #endif
2207
2208 static __inline void
2209 ng_leave_read(struct ng_queue *ngq)
2210 {
2211 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT);
2212 }
2213
2214 static __inline void
2215 ng_leave_write(struct ng_queue *ngq)
2216 {
2217 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE);
2218 }
2219
2220 static void
2221 ng_flush_input_queue(struct ng_queue * ngq)
2222 {
2223 item_p item;
2224
2225 NG_QUEUE_LOCK(ngq);
2226 while (ngq->queue) {
2227 item = ngq->queue;
2228 ngq->queue = item->el_next;
2229 if (ngq->last == &(item->el_next)) {
2230 ngq->last = &(ngq->queue);
2231 atomic_add_long(&ngq->q_flags, -OP_PENDING);
2232 }
2233 NG_QUEUE_UNLOCK(ngq);
2234
2235 /* If the item is supplying a callback, call it with an error */
2236 if (item->apply != NULL &&
2237 refcount_release(&item->apply->refs)) {
2238 (*item->apply->apply)(item->apply->context, ENOENT);
2239 }
2240 NG_FREE_ITEM(item);
2241 NG_QUEUE_LOCK(ngq);
2242 }
2243 /*
2244 * Take us off the work queue if we are there.
2245 * We definately have no work to be done.
2246 */
2247 ng_worklist_remove(ngq->q_node);
2248 NG_QUEUE_UNLOCK(ngq);
2249 }
2250
2251 /***********************************************************************
2252 * Externally visible method for sending or queueing messages or data.
2253 ***********************************************************************/
2254
2255 /*
2256 * The module code should have filled out the item correctly by this stage:
2257 * Common:
2258 * reference to destination node.
2259 * Reference to destination rcv hook if relevant.
2260 * apply pointer must be or NULL or reference valid struct ng_apply_info.
2261 * Data:
2262 * pointer to mbuf
2263 * Control_Message:
2264 * pointer to msg.
2265 * ID of original sender node. (return address)
2266 * Function:
2267 * Function pointer
2268 * void * argument
2269 * integer argument
2270 *
2271 * The nodes have several routines and macros to help with this task:
2272 */
2273
2274 int
2275 ng_snd_item(item_p item, int flags)
2276 {
2277 hook_p hook;
2278 node_p node;
2279 int queue, rw;
2280 struct ng_queue *ngq;
2281 int error = 0;
2282
2283 if (item == NULL) {
2284 TRAP_ERROR();
2285 return (EINVAL); /* failed to get queue element */
2286 }
2287
2288 #ifdef NETGRAPH_DEBUG
2289 _ngi_check(item, __FILE__, __LINE__);
2290 #endif
2291
2292 if (item->apply)
2293 refcount_acquire(&item->apply->refs);
2294
2295 hook = NGI_HOOK(item);
2296 node = NGI_NODE(item);
2297 ngq = &node->nd_input_queue;
2298 if (node == NULL) {
2299 TRAP_ERROR();
2300 ERROUT(EINVAL); /* No address */
2301 }
2302
2303 queue = (flags & NG_QUEUE) ? 1 : 0;
2304
2305 switch(item->el_flags & NGQF_TYPE) {
2306 case NGQF_DATA:
2307 /*
2308 * DATA MESSAGE
2309 * Delivered to a node via a non-optional hook.
2310 * Both should be present in the item even though
2311 * the node is derivable from the hook.
2312 * References are held on both by the item.
2313 */
2314
2315 /* Protect nodes from sending NULL pointers
2316 * to each other
2317 */
2318 if (NGI_M(item) == NULL)
2319 ERROUT(EINVAL);
2320
2321 CHECK_DATA_MBUF(NGI_M(item));
2322 if (hook == NULL) {
2323 TRAP_ERROR();
2324 ERROUT(EINVAL);
2325 }
2326 if ((NG_HOOK_NOT_VALID(hook))
2327 || (NG_NODE_NOT_VALID(NG_HOOK_NODE(hook)))) {
2328 ERROUT(ENOTCONN);
2329 }
2330 if ((hook->hk_flags & HK_QUEUE)) {
2331 queue = 1;
2332 }
2333 break;
2334 case NGQF_MESG:
2335 /*
2336 * CONTROL MESSAGE
2337 * Delivered to a node.
2338 * Hook is optional.
2339 * References are held by the item on the node and
2340 * the hook if it is present.
2341 */
2342 if (hook && (hook->hk_flags & HK_QUEUE)) {
2343 queue = 1;
2344 }
2345 break;
2346 case NGQF_FN:
2347 case NGQF_FN2:
2348 break;
2349 default:
2350 TRAP_ERROR();
2351 ERROUT(EINVAL);
2352 }
2353 switch(item->el_flags & NGQF_RW) {
2354 case NGQF_READER:
2355 rw = NGQRW_R;
2356 break;
2357 case NGQF_WRITER:
2358 rw = NGQRW_W;
2359 break;
2360 default:
2361 panic("%s: invalid item flags %lx", __func__, item->el_flags);
2362 }
2363
2364 /*
2365 * If the node specifies single threading, force writer semantics.
2366 * Similarly, the node may say one hook always produces writers.
2367 * These are overrides.
2368 */
2369 if ((node->nd_flags & NGF_FORCE_WRITER)
2370 || (hook && (hook->hk_flags & HK_FORCE_WRITER)))
2371 rw = NGQRW_W;
2372
2373 if (queue) {
2374 /* Put it on the queue for that node*/
2375 #ifdef NETGRAPH_DEBUG
2376 _ngi_check(item, __FILE__, __LINE__);
2377 #endif
2378 NG_QUEUE_LOCK(ngq);
2379 ng_queue_rw(ngq, item, rw);
2380 NG_QUEUE_UNLOCK(ngq);
2381
2382 if (flags & NG_PROGRESS)
2383 return (EINPROGRESS);
2384 else
2385 return (0);
2386 }
2387
2388 /*
2389 * We already decided how we will be queueud or treated.
2390 * Try get the appropriate operating permission.
2391 */
2392 if (rw == NGQRW_R)
2393 item = ng_acquire_read(ngq, item);
2394 else
2395 item = ng_acquire_write(ngq, item);
2396
2397
2398 if (item == NULL) {
2399 if (flags & NG_PROGRESS)
2400 return (EINPROGRESS);
2401 else
2402 return (0);
2403 }
2404
2405 #ifdef NETGRAPH_DEBUG
2406 _ngi_check(item, __FILE__, __LINE__);
2407 #endif
2408
2409 NGI_GET_NODE(item, node); /* zaps stored node */
2410
2411 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */
2412
2413 /*
2414 * If the node goes away when we remove the reference,
2415 * whatever we just did caused it.. whatever we do, DO NOT
2416 * access the node again!
2417 */
2418 if (NG_NODE_UNREF(node) == 0) {
2419 return (error);
2420 }
2421
2422 NG_QUEUE_LOCK(ngq);
2423 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2424 ng_setisr(ngq->q_node);
2425 NG_QUEUE_UNLOCK(ngq);
2426
2427 return (error);
2428
2429 done:
2430 /* Apply callback. */
2431 if (item->apply != NULL &&
2432 refcount_release(&item->apply->refs)) {
2433 (*item->apply->apply)(item->apply->context, error);
2434 }
2435 NG_FREE_ITEM(item);
2436 return (error);
2437 }
2438
2439 /*
2440 * We have an item that was possibly queued somewhere.
2441 * It should contain all the information needed
2442 * to run it on the appropriate node/hook.
2443 * If there is apply pointer and we own the last reference, call apply().
2444 */
2445 static int
2446 ng_apply_item(node_p node, item_p item, int rw)
2447 {
2448 hook_p hook;
2449 int error = 0;
2450 ng_rcvdata_t *rcvdata;
2451 ng_rcvmsg_t *rcvmsg;
2452 struct ng_apply_info *apply;
2453
2454 NGI_GET_HOOK(item, hook); /* clears stored hook */
2455 #ifdef NETGRAPH_DEBUG
2456 _ngi_check(item, __FILE__, __LINE__);
2457 #endif
2458
2459 apply = item->apply;
2460
2461 switch (item->el_flags & NGQF_TYPE) {
2462 case NGQF_DATA:
2463 /*
2464 * Check things are still ok as when we were queued.
2465 */
2466 if ((hook == NULL)
2467 || NG_HOOK_NOT_VALID(hook)
2468 || NG_NODE_NOT_VALID(node) ) {
2469 error = EIO;
2470 NG_FREE_ITEM(item);
2471 break;
2472 }
2473 /*
2474 * If no receive method, just silently drop it.
2475 * Give preference to the hook over-ride method
2476 */
2477 if ((!(rcvdata = hook->hk_rcvdata))
2478 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) {
2479 error = 0;
2480 NG_FREE_ITEM(item);
2481 break;
2482 }
2483 error = (*rcvdata)(hook, item);
2484 break;
2485 case NGQF_MESG:
2486 if (hook) {
2487 if (NG_HOOK_NOT_VALID(hook)) {
2488 /*
2489 * The hook has been zapped then we can't
2490 * use it. Immediately drop its reference.
2491 * The message may not need it.
2492 */
2493 NG_HOOK_UNREF(hook);
2494 hook = NULL;
2495 }
2496 }
2497 /*
2498 * Similarly, if the node is a zombie there is
2499 * nothing we can do with it, drop everything.
2500 */
2501 if (NG_NODE_NOT_VALID(node)) {
2502 TRAP_ERROR();
2503 error = EINVAL;
2504 NG_FREE_ITEM(item);
2505 } else {
2506 /*
2507 * Call the appropriate message handler for the object.
2508 * It is up to the message handler to free the message.
2509 * If it's a generic message, handle it generically,
2510 * otherwise call the type's message handler
2511 * (if it exists)
2512 * XXX (race). Remember that a queued message may
2513 * reference a node or hook that has just been
2514 * invalidated. It will exist as the queue code
2515 * is holding a reference, but..
2516 */
2517
2518 struct ng_mesg *msg = NGI_MSG(item);
2519
2520 /*
2521 * check if the generic handler owns it.
2522 */
2523 if ((msg->header.typecookie == NGM_GENERIC_COOKIE)
2524 && ((msg->header.flags & NGF_RESP) == 0)) {
2525 error = ng_generic_msg(node, item, hook);
2526 break;
2527 }
2528 /*
2529 * Now see if there is a handler (hook or node specific)
2530 * in the target node. If none, silently discard.
2531 */
2532 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg)))
2533 && (!(rcvmsg = node->nd_type->rcvmsg))) {
2534 TRAP_ERROR();
2535 error = 0;
2536 NG_FREE_ITEM(item);
2537 break;
2538 }
2539 error = (*rcvmsg)(node, item, hook);
2540 }
2541 break;
2542 case NGQF_FN:
2543 case NGQF_FN2:
2544 /*
2545 * We have to implicitly trust the hook,
2546 * as some of these are used for system purposes
2547 * where the hook is invalid. In the case of
2548 * the shutdown message we allow it to hit
2549 * even if the node is invalid.
2550 */
2551 if ((NG_NODE_NOT_VALID(node))
2552 && (NGI_FN(item) != &ng_rmnode)) {
2553 TRAP_ERROR();
2554 error = EINVAL;
2555 NG_FREE_ITEM(item);
2556 break;
2557 }
2558 if ((item->el_flags & NGQF_TYPE) == NGQF_FN) {
2559 (*NGI_FN(item))(node, hook, NGI_ARG1(item),
2560 NGI_ARG2(item));
2561 NG_FREE_ITEM(item);
2562 } else /* it is NGQF_FN2 */
2563 error = (*NGI_FN2(item))(node, item, hook);
2564 break;
2565 }
2566 /*
2567 * We held references on some of the resources
2568 * that we took from the item. Now that we have
2569 * finished doing everything, drop those references.
2570 */
2571 if (hook) {
2572 NG_HOOK_UNREF(hook);
2573 }
2574
2575 if (rw == NGQRW_R) {
2576 ng_leave_read(&node->nd_input_queue);
2577 } else {
2578 ng_leave_write(&node->nd_input_queue);
2579 }
2580
2581 /* Apply callback. */
2582 if (apply != NULL &&
2583 refcount_release(&apply->refs)) {
2584 (*apply->apply)(apply->context, error);
2585 }
2586
2587 return (error);
2588 }
2589
2590 /***********************************************************************
2591 * Implement the 'generic' control messages
2592 ***********************************************************************/
2593 static int
2594 ng_generic_msg(node_p here, item_p item, hook_p lasthook)
2595 {
2596 int error = 0;
2597 struct ng_mesg *msg;
2598 struct ng_mesg *resp = NULL;
2599
2600 NGI_GET_MSG(item, msg);
2601 if (msg->header.typecookie != NGM_GENERIC_COOKIE) {
2602 TRAP_ERROR();
2603 error = EINVAL;
2604 goto out;
2605 }
2606 switch (msg->header.cmd) {
2607 case NGM_SHUTDOWN:
2608 ng_rmnode(here, NULL, NULL, 0);
2609 break;
2610 case NGM_MKPEER:
2611 {
2612 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
2613
2614 if (msg->header.arglen != sizeof(*mkp)) {
2615 TRAP_ERROR();
2616 error = EINVAL;
2617 break;
2618 }
2619 mkp->type[sizeof(mkp->type) - 1] = '\0';
2620 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0';
2621 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0';
2622 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type);
2623 break;
2624 }
2625 case NGM_CONNECT:
2626 {
2627 struct ngm_connect *const con =
2628 (struct ngm_connect *) msg->data;
2629 node_p node2;
2630
2631 if (msg->header.arglen != sizeof(*con)) {
2632 TRAP_ERROR();
2633 error = EINVAL;
2634 break;
2635 }
2636 con->path[sizeof(con->path) - 1] = '\0';
2637 con->ourhook[sizeof(con->ourhook) - 1] = '\0';
2638 con->peerhook[sizeof(con->peerhook) - 1] = '\0';
2639 /* Don't forget we get a reference.. */
2640 error = ng_path2noderef(here, con->path, &node2, NULL);
2641 if (error)
2642 break;
2643 error = ng_con_nodes(item, here, con->ourhook,
2644 node2, con->peerhook);
2645 NG_NODE_UNREF(node2);
2646 break;
2647 }
2648 case NGM_NAME:
2649 {
2650 struct ngm_name *const nam = (struct ngm_name *) msg->data;
2651
2652 if (msg->header.arglen != sizeof(*nam)) {
2653 TRAP_ERROR();
2654 error = EINVAL;
2655 break;
2656 }
2657 nam->name[sizeof(nam->name) - 1] = '\0';
2658 error = ng_name_node(here, nam->name);
2659 break;
2660 }
2661 case NGM_RMHOOK:
2662 {
2663 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data;
2664 hook_p hook;
2665
2666 if (msg->header.arglen != sizeof(*rmh)) {
2667 TRAP_ERROR();
2668 error = EINVAL;
2669 break;
2670 }
2671 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0';
2672 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL)
2673 ng_destroy_hook(hook);
2674 break;
2675 }
2676 case NGM_NODEINFO:
2677 {
2678 struct nodeinfo *ni;
2679
2680 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT);
2681 if (resp == NULL) {
2682 error = ENOMEM;
2683 break;
2684 }
2685
2686 /* Fill in node info */
2687 ni = (struct nodeinfo *) resp->data;
2688 if (NG_NODE_HAS_NAME(here))
2689 strcpy(ni->name, NG_NODE_NAME(here));
2690 strcpy(ni->type, here->nd_type->name);
2691 ni->id = ng_node2ID(here);
2692 ni->hooks = here->nd_numhooks;
2693 break;
2694 }
2695 case NGM_LISTHOOKS:
2696 {
2697 const int nhooks = here->nd_numhooks;
2698 struct hooklist *hl;
2699 struct nodeinfo *ni;
2700 hook_p hook;
2701
2702 /* Get response struct */
2703 NG_MKRESPONSE(resp, msg, sizeof(*hl)
2704 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT);
2705 if (resp == NULL) {
2706 error = ENOMEM;
2707 break;
2708 }
2709 hl = (struct hooklist *) resp->data;
2710 ni = &hl->nodeinfo;
2711
2712 /* Fill in node info */
2713 if (NG_NODE_HAS_NAME(here))
2714 strcpy(ni->name, NG_NODE_NAME(here));
2715 strcpy(ni->type, here->nd_type->name);
2716 ni->id = ng_node2ID(here);
2717
2718 /* Cycle through the linked list of hooks */
2719 ni->hooks = 0;
2720 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) {
2721 struct linkinfo *const link = &hl->link[ni->hooks];
2722
2723 if (ni->hooks >= nhooks) {
2724 log(LOG_ERR, "%s: number of %s changed\n",
2725 __func__, "hooks");
2726 break;
2727 }
2728 if (NG_HOOK_NOT_VALID(hook))
2729 continue;
2730 strcpy(link->ourhook, NG_HOOK_NAME(hook));
2731 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook));
2732 if (NG_PEER_NODE_NAME(hook)[0] != '\0')
2733 strcpy(link->nodeinfo.name,
2734 NG_PEER_NODE_NAME(hook));
2735 strcpy(link->nodeinfo.type,
2736 NG_PEER_NODE(hook)->nd_type->name);
2737 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook));
2738 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks;
2739 ni->hooks++;
2740 }
2741 break;
2742 }
2743
2744 case NGM_LISTNAMES:
2745 case NGM_LISTNODES:
2746 {
2747 const int unnamed = (msg->header.cmd == NGM_LISTNODES);
2748 struct namelist *nl;
2749 node_p node;
2750 int num = 0;
2751
2752 mtx_lock(&ng_nodelist_mtx);
2753 /* Count number of nodes */
2754 LIST_FOREACH(node, &ng_nodelist, nd_nodes) {
2755 if (NG_NODE_IS_VALID(node)
2756 && (unnamed || NG_NODE_HAS_NAME(node))) {
2757 num++;
2758 }
2759 }
2760 mtx_unlock(&ng_nodelist_mtx);
2761
2762 /* Get response struct */
2763 NG_MKRESPONSE(resp, msg, sizeof(*nl)
2764 + (num * sizeof(struct nodeinfo)), M_NOWAIT);
2765 if (resp == NULL) {
2766 error = ENOMEM;
2767 break;
2768 }
2769 nl = (struct namelist *) resp->data;
2770
2771 /* Cycle through the linked list of nodes */
2772 nl->numnames = 0;
2773 mtx_lock(&ng_nodelist_mtx);
2774 LIST_FOREACH(node, &ng_nodelist, nd_nodes) {
2775 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames];
2776
2777 if (NG_NODE_NOT_VALID(node))
2778 continue;
2779 if (!unnamed && (! NG_NODE_HAS_NAME(node)))
2780 continue;
2781 if (nl->numnames >= num) {
2782 log(LOG_ERR, "%s: number of %s changed\n",
2783 __func__, "nodes");
2784 break;
2785 }
2786 if (NG_NODE_HAS_NAME(node))
2787 strcpy(np->name, NG_NODE_NAME(node));
2788 strcpy(np->type, node->nd_type->name);
2789 np->id = ng_node2ID(node);
2790 np->hooks = node->nd_numhooks;
2791 nl->numnames++;
2792 }
2793 mtx_unlock(&ng_nodelist_mtx);
2794 break;
2795 }
2796
2797 case NGM_LISTTYPES:
2798 {
2799 struct typelist *tl;
2800 struct ng_type *type;
2801 int num = 0;
2802
2803 mtx_lock(&ng_typelist_mtx);
2804 /* Count number of types */
2805 LIST_FOREACH(type, &ng_typelist, types) {
2806 num++;
2807 }
2808 mtx_unlock(&ng_typelist_mtx);
2809
2810 /* Get response struct */
2811 NG_MKRESPONSE(resp, msg, sizeof(*tl)
2812 + (num * sizeof(struct typeinfo)), M_NOWAIT);
2813 if (resp == NULL) {
2814 error = ENOMEM;
2815 break;
2816 }
2817 tl = (struct typelist *) resp->data;
2818
2819 /* Cycle through the linked list of types */
2820 tl->numtypes = 0;
2821 mtx_lock(&ng_typelist_mtx);
2822 LIST_FOREACH(type, &ng_typelist, types) {
2823 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes];
2824
2825 if (tl->numtypes >= num) {
2826 log(LOG_ERR, "%s: number of %s changed\n",
2827 __func__, "types");
2828 break;
2829 }
2830 strcpy(tp->type_name, type->name);
2831 tp->numnodes = type->refs - 1; /* don't count list */
2832 tl->numtypes++;
2833 }
2834 mtx_unlock(&ng_typelist_mtx);
2835 break;
2836 }
2837
2838 case NGM_BINARY2ASCII:
2839 {
2840 int bufSize = 20 * 1024; /* XXX hard coded constant */
2841 const struct ng_parse_type *argstype;
2842 const struct ng_cmdlist *c;
2843 struct ng_mesg *binary, *ascii;
2844
2845 /* Data area must contain a valid netgraph message */
2846 binary = (struct ng_mesg *)msg->data;
2847 if (msg->header.arglen < sizeof(struct ng_mesg) ||
2848 (msg->header.arglen - sizeof(struct ng_mesg) <
2849 binary->header.arglen)) {
2850 TRAP_ERROR();
2851 error = EINVAL;
2852 break;
2853 }
2854
2855 /* Get a response message with lots of room */
2856 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT);
2857 if (resp == NULL) {
2858 error = ENOMEM;
2859 break;
2860 }
2861 ascii = (struct ng_mesg *)resp->data;
2862
2863 /* Copy binary message header to response message payload */
2864 bcopy(binary, ascii, sizeof(*binary));
2865
2866 /* Find command by matching typecookie and command number */
2867 for (c = here->nd_type->cmdlist;
2868 c != NULL && c->name != NULL; c++) {
2869 if (binary->header.typecookie == c->cookie
2870 && binary->header.cmd == c->cmd)
2871 break;
2872 }
2873 if (c == NULL || c->name == NULL) {
2874 for (c = ng_generic_cmds; c->name != NULL; c++) {
2875 if (binary->header.typecookie == c->cookie
2876 && binary->header.cmd == c->cmd)
2877 break;
2878 }
2879 if (c->name == NULL) {
2880 NG_FREE_MSG(resp);
2881 error = ENOSYS;
2882 break;
2883 }
2884 }
2885
2886 /* Convert command name to ASCII */
2887 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr),
2888 "%s", c->name);
2889
2890 /* Convert command arguments to ASCII */
2891 argstype = (binary->header.flags & NGF_RESP) ?
2892 c->respType : c->mesgType;
2893 if (argstype == NULL) {
2894 *ascii->data = '\0';
2895 } else {
2896 if ((error = ng_unparse(argstype,
2897 (u_char *)binary->data,
2898 ascii->data, bufSize)) != 0) {
2899 NG_FREE_MSG(resp);
2900 break;
2901 }
2902 }
2903
2904 /* Return the result as struct ng_mesg plus ASCII string */
2905 bufSize = strlen(ascii->data) + 1;
2906 ascii->header.arglen = bufSize;
2907 resp->header.arglen = sizeof(*ascii) + bufSize;
2908 break;
2909 }
2910
2911 case NGM_ASCII2BINARY:
2912 {
2913 int bufSize = 2000; /* XXX hard coded constant */
2914 const struct ng_cmdlist *c;
2915 const struct ng_parse_type *argstype;
2916 struct ng_mesg *ascii, *binary;
2917 int off = 0;
2918
2919 /* Data area must contain at least a struct ng_mesg + '\0' */
2920 ascii = (struct ng_mesg *)msg->data;
2921 if ((msg->header.arglen < sizeof(*ascii) + 1) ||
2922 (ascii->header.arglen < 1) ||
2923 (msg->header.arglen < sizeof(*ascii) +
2924 ascii->header.arglen)) {
2925 TRAP_ERROR();
2926 error = EINVAL;
2927 break;
2928 }
2929 ascii->data[ascii->header.arglen - 1] = '\0';
2930
2931 /* Get a response message with lots of room */
2932 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT);
2933 if (resp == NULL) {
2934 error = ENOMEM;
2935 break;
2936 }
2937 binary = (struct ng_mesg *)resp->data;
2938
2939 /* Copy ASCII message header to response message payload */
2940 bcopy(ascii, binary, sizeof(*ascii));
2941
2942 /* Find command by matching ASCII command string */
2943 for (c = here->nd_type->cmdlist;
2944 c != NULL && c->name != NULL; c++) {
2945 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2946 break;
2947 }
2948 if (c == NULL || c->name == NULL) {
2949 for (c = ng_generic_cmds; c->name != NULL; c++) {
2950 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2951 break;
2952 }
2953 if (c->name == NULL) {
2954 NG_FREE_MSG(resp);
2955 error = ENOSYS;
2956 break;
2957 }
2958 }
2959
2960 /* Convert command name to binary */
2961 binary->header.cmd = c->cmd;
2962 binary->header.typecookie = c->cookie;
2963
2964 /* Convert command arguments to binary */
2965 argstype = (binary->header.flags & NGF_RESP) ?
2966 c->respType : c->mesgType;
2967 if (argstype == NULL) {
2968 bufSize = 0;
2969 } else {
2970 if ((error = ng_parse(argstype, ascii->data,
2971 &off, (u_char *)binary->data, &bufSize)) != 0) {
2972 NG_FREE_MSG(resp);
2973 break;
2974 }
2975 }
2976
2977 /* Return the result */
2978 binary->header.arglen = bufSize;
2979 resp->header.arglen = sizeof(*binary) + bufSize;
2980 break;
2981 }
2982
2983 case NGM_TEXT_CONFIG:
2984 case NGM_TEXT_STATUS:
2985 /*
2986 * This one is tricky as it passes the command down to the
2987 * actual node, even though it is a generic type command.
2988 * This means we must assume that the item/msg is already freed
2989 * when control passes back to us.
2990 */
2991 if (here->nd_type->rcvmsg != NULL) {
2992 NGI_MSG(item) = msg; /* put it back as we found it */
2993 return((*here->nd_type->rcvmsg)(here, item, lasthook));
2994 }
2995 /* Fall through if rcvmsg not supported */
2996 default:
2997 TRAP_ERROR();
2998 error = EINVAL;
2999 }
3000 /*
3001 * Sometimes a generic message may be statically allocated
3002 * to avoid problems with allocating when in tight memeory situations.
3003 * Don't free it if it is so.
3004 * I break them appart here, because erros may cause a free if the item
3005 * in which case we'd be doing it twice.
3006 * they are kept together above, to simplify freeing.
3007 */
3008 out:
3009 NG_RESPOND_MSG(error, here, item, resp);
3010 if (msg)
3011 NG_FREE_MSG(msg);
3012 return (error);
3013 }
3014
3015 /************************************************************************
3016 Queue element get/free routines
3017 ************************************************************************/
3018
3019 uma_zone_t ng_qzone;
3020 static int maxalloc = 512; /* limit the damage of a leak */
3021
3022 TUNABLE_INT("net.graph.maxalloc", &maxalloc);
3023 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc,
3024 0, "Maximum number of queue items to allocate");
3025
3026 #ifdef NETGRAPH_DEBUG
3027 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist);
3028 static int allocated; /* number of items malloc'd */
3029 #endif
3030
3031 /*
3032 * Get a queue entry.
3033 * This is usually called when a packet first enters netgraph.
3034 * By definition, this is usually from an interrupt, or from a user.
3035 * Users are not so important, but try be quick for the times that it's
3036 * an interrupt.
3037 */
3038 static __inline item_p
3039 ng_getqblk(int flags)
3040 {
3041 item_p item = NULL;
3042 int wait;
3043
3044 wait = (flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT;
3045
3046 item = uma_zalloc(ng_qzone, wait | M_ZERO);
3047
3048 #ifdef NETGRAPH_DEBUG
3049 if (item) {
3050 mtx_lock(&ngq_mtx);
3051 TAILQ_INSERT_TAIL(&ng_itemlist, item, all);
3052 allocated++;
3053 mtx_unlock(&ngq_mtx);
3054 }
3055 #endif
3056
3057 return (item);
3058 }
3059
3060 /*
3061 * Release a queue entry
3062 */
3063 void
3064 ng_free_item(item_p item)
3065 {
3066 /*
3067 * The item may hold resources on it's own. We need to free
3068 * these before we can free the item. What they are depends upon
3069 * what kind of item it is. it is important that nodes zero
3070 * out pointers to resources that they remove from the item
3071 * or we release them again here.
3072 */
3073 switch (item->el_flags & NGQF_TYPE) {
3074 case NGQF_DATA:
3075 /* If we have an mbuf still attached.. */
3076 NG_FREE_M(_NGI_M(item));
3077 break;
3078 case NGQF_MESG:
3079 _NGI_RETADDR(item) = 0;
3080 NG_FREE_MSG(_NGI_MSG(item));
3081 break;
3082 case NGQF_FN:
3083 case NGQF_FN2:
3084 /* nothing to free really, */
3085 _NGI_FN(item) = NULL;
3086 _NGI_ARG1(item) = NULL;
3087 _NGI_ARG2(item) = 0;
3088 break;
3089 }
3090 /* If we still have a node or hook referenced... */
3091 _NGI_CLR_NODE(item);
3092 _NGI_CLR_HOOK(item);
3093
3094 #ifdef NETGRAPH_DEBUG
3095 mtx_lock(&ngq_mtx);
3096 TAILQ_REMOVE(&ng_itemlist, item, all);
3097 allocated--;
3098 mtx_unlock(&ngq_mtx);
3099 #endif
3100 uma_zfree(ng_qzone, item);
3101 }
3102
3103 /************************************************************************
3104 Module routines
3105 ************************************************************************/
3106
3107 /*
3108 * Handle the loading/unloading of a netgraph node type module
3109 */
3110 int
3111 ng_mod_event(module_t mod, int event, void *data)
3112 {
3113 struct ng_type *const type = data;
3114 int s, error = 0;
3115
3116 switch (event) {
3117 case MOD_LOAD:
3118
3119 /* Register new netgraph node type */
3120 s = splnet();
3121 if ((error = ng_newtype(type)) != 0) {
3122 splx(s);
3123 break;
3124 }
3125
3126 /* Call type specific code */
3127 if (type->mod_event != NULL)
3128 if ((error = (*type->mod_event)(mod, event, data))) {
3129 mtx_lock(&ng_typelist_mtx);
3130 type->refs--; /* undo it */
3131 LIST_REMOVE(type, types);
3132 mtx_unlock(&ng_typelist_mtx);
3133 }
3134 splx(s);
3135 break;
3136
3137 case MOD_UNLOAD:
3138 s = splnet();
3139 if (type->refs > 1) { /* make sure no nodes exist! */
3140 error = EBUSY;
3141 } else {
3142 if (type->refs == 0) {
3143 /* failed load, nothing to undo */
3144 splx(s);
3145 break;
3146 }
3147 if (type->mod_event != NULL) { /* check with type */
3148 error = (*type->mod_event)(mod, event, data);
3149 if (error != 0) { /* type refuses.. */
3150 splx(s);
3151 break;
3152 }
3153 }
3154 mtx_lock(&ng_typelist_mtx);
3155 LIST_REMOVE(type, types);
3156 mtx_unlock(&ng_typelist_mtx);
3157 }
3158 splx(s);
3159 break;
3160
3161 default:
3162 if (type->mod_event != NULL)
3163 error = (*type->mod_event)(mod, event, data);
3164 else
3165 error = EOPNOTSUPP; /* XXX ? */
3166 break;
3167 }
3168 return (error);
3169 }
3170
3171 /*
3172 * Handle loading and unloading for this code.
3173 * The only thing we need to link into is the NETISR strucure.
3174 */
3175 static int
3176 ngb_mod_event(module_t mod, int event, void *data)
3177 {
3178 int error = 0;
3179
3180 switch (event) {
3181 case MOD_LOAD:
3182 /* Initialize everything. */
3183 NG_WORKLIST_LOCK_INIT();
3184 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL,
3185 MTX_DEF);
3186 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL,
3187 MTX_DEF);
3188 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL,
3189 MTX_DEF);
3190 mtx_init(&ng_topo_mtx, "netgraph topology mutex", NULL,
3191 MTX_DEF);
3192 #ifdef NETGRAPH_DEBUG
3193 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL,
3194 MTX_DEF);
3195 #endif
3196 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item),
3197 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
3198 uma_zone_set_max(ng_qzone, maxalloc);
3199 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL,
3200 NETISR_MPSAFE);
3201 break;
3202 case MOD_UNLOAD:
3203 /* You can't unload it because an interface may be using it. */
3204 error = EBUSY;
3205 break;
3206 default:
3207 error = EOPNOTSUPP;
3208 break;
3209 }
3210 return (error);
3211 }
3212
3213 static moduledata_t netgraph_mod = {
3214 "netgraph",
3215 ngb_mod_event,
3216 (NULL)
3217 };
3218 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE);
3219 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family");
3220 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,"");
3221 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, "");
3222
3223 #ifdef NETGRAPH_DEBUG
3224 void
3225 dumphook (hook_p hook, char *file, int line)
3226 {
3227 printf("hook: name %s, %d refs, Last touched:\n",
3228 _NG_HOOK_NAME(hook), hook->hk_refs);
3229 printf(" Last active @ %s, line %d\n",
3230 hook->lastfile, hook->lastline);
3231 if (line) {
3232 printf(" problem discovered at file %s, line %d\n", file, line);
3233 }
3234 }
3235
3236 void
3237 dumpnode(node_p node, char *file, int line)
3238 {
3239 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n",
3240 _NG_NODE_ID(node), node->nd_type->name,
3241 node->nd_numhooks, node->nd_flags,
3242 node->nd_refs, node->nd_name);
3243 printf(" Last active @ %s, line %d\n",
3244 node->lastfile, node->lastline);
3245 if (line) {
3246 printf(" problem discovered at file %s, line %d\n", file, line);
3247 }
3248 }
3249
3250 void
3251 dumpitem(item_p item, char *file, int line)
3252 {
3253 printf(" ACTIVE item, last used at %s, line %d",
3254 item->lastfile, item->lastline);
3255 switch(item->el_flags & NGQF_TYPE) {
3256 case NGQF_DATA:
3257 printf(" - [data]\n");
3258 break;
3259 case NGQF_MESG:
3260 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item));
3261 break;
3262 case NGQF_FN:
3263 printf(" - fn@%p (%p, %p, %p, %d (%x))\n",
3264 _NGI_FN(item),
3265 _NGI_NODE(item),
3266 _NGI_HOOK(item),
3267 item->body.fn.fn_arg1,
3268 item->body.fn.fn_arg2,
3269 item->body.fn.fn_arg2);
3270 break;
3271 case NGQF_FN2:
3272 printf(" - fn2@%p (%p, %p, %p, %d (%x))\n",
3273 _NGI_FN2(item),
3274 _NGI_NODE(item),
3275 _NGI_HOOK(item),
3276 item->body.fn.fn_arg1,
3277 item->body.fn.fn_arg2,
3278 item->body.fn.fn_arg2);
3279 break;
3280 }
3281 if (line) {
3282 printf(" problem discovered at file %s, line %d\n", file, line);
3283 if (_NGI_NODE(item)) {
3284 printf("node %p ([%x])\n",
3285 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item)));
3286 }
3287 }
3288 }
3289
3290 static void
3291 ng_dumpitems(void)
3292 {
3293 item_p item;
3294 int i = 1;
3295 TAILQ_FOREACH(item, &ng_itemlist, all) {
3296 printf("[%d] ", i++);
3297 dumpitem(item, NULL, 0);
3298 }
3299 }
3300
3301 static void
3302 ng_dumpnodes(void)
3303 {
3304 node_p node;
3305 int i = 1;
3306 mtx_lock(&ng_nodelist_mtx);
3307 SLIST_FOREACH(node, &ng_allnodes, nd_all) {
3308 printf("[%d] ", i++);
3309 dumpnode(node, NULL, 0);
3310 }
3311 mtx_unlock(&ng_nodelist_mtx);
3312 }
3313
3314 static void
3315 ng_dumphooks(void)
3316 {
3317 hook_p hook;
3318 int i = 1;
3319 mtx_lock(&ng_nodelist_mtx);
3320 SLIST_FOREACH(hook, &ng_allhooks, hk_all) {
3321 printf("[%d] ", i++);
3322 dumphook(hook, NULL, 0);
3323 }
3324 mtx_unlock(&ng_nodelist_mtx);
3325 }
3326
3327 static int
3328 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS)
3329 {
3330 int error;
3331 int val;
3332 int i;
3333
3334 val = allocated;
3335 i = 1;
3336 error = sysctl_handle_int(oidp, &val, 0, req);
3337 if (error != 0 || req->newptr == NULL)
3338 return (error);
3339 if (val == 42) {
3340 ng_dumpitems();
3341 ng_dumpnodes();
3342 ng_dumphooks();
3343 }
3344 return (0);
3345 }
3346
3347 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW,
3348 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items");
3349 #endif /* NETGRAPH_DEBUG */
3350
3351
3352 /***********************************************************************
3353 * Worklist routines
3354 **********************************************************************/
3355 /* NETISR thread enters here */
3356 /*
3357 * Pick a node off the list of nodes with work,
3358 * try get an item to process off it.
3359 * If there are no more, remove the node from the list.
3360 */
3361 static void
3362 ngintr(void)
3363 {
3364 item_p item;
3365 node_p node = NULL;
3366
3367 for (;;) {
3368 NG_WORKLIST_LOCK();
3369 node = TAILQ_FIRST(&ng_worklist);
3370 if (!node) {
3371 NG_WORKLIST_UNLOCK();
3372 break;
3373 }
3374 node->nd_flags &= ~NGF_WORKQ;
3375 TAILQ_REMOVE(&ng_worklist, node, nd_work);
3376 NG_WORKLIST_UNLOCK();
3377 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist",
3378 __func__, node->nd_ID, node);
3379 /*
3380 * We have the node. We also take over the reference
3381 * that the list had on it.
3382 * Now process as much as you can, until it won't
3383 * let you have another item off the queue.
3384 * All this time, keep the reference
3385 * that lets us be sure that the node still exists.
3386 * Let the reference go at the last minute.
3387 * ng_dequeue will put us back on the worklist
3388 * if there is more too do. This may be of use if there
3389 * are Multiple Processors and multiple Net threads in the
3390 * future.
3391 */
3392 for (;;) {
3393 int rw;
3394
3395 NG_QUEUE_LOCK(&node->nd_input_queue);
3396 item = ng_dequeue(&node->nd_input_queue, &rw);
3397 if (item == NULL) {
3398 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3399 break; /* go look for another node */
3400 } else {
3401 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3402 NGI_GET_NODE(item, node); /* zaps stored node */
3403 ng_apply_item(node, item, rw);
3404 NG_NODE_UNREF(node);
3405 }
3406 }
3407 NG_NODE_UNREF(node);
3408 }
3409 }
3410
3411 static void
3412 ng_worklist_remove(node_p node)
3413 {
3414 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED);
3415
3416 NG_WORKLIST_LOCK();
3417 if (node->nd_flags & NGF_WORKQ) {
3418 node->nd_flags &= ~NGF_WORKQ;
3419 TAILQ_REMOVE(&ng_worklist, node, nd_work);
3420 NG_WORKLIST_UNLOCK();
3421 NG_NODE_UNREF(node);
3422 CTR3(KTR_NET, "%20s: node [%x] (%p) removed from worklist",
3423 __func__, node->nd_ID, node);
3424 } else {
3425 NG_WORKLIST_UNLOCK();
3426 }
3427 }
3428
3429 /*
3430 * XXX
3431 * It's posible that a debugging NG_NODE_REF may need
3432 * to be outside the mutex zone
3433 */
3434 static void
3435 ng_setisr(node_p node)
3436 {
3437
3438 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED);
3439
3440 if ((node->nd_flags & NGF_WORKQ) == 0) {
3441 /*
3442 * If we are not already on the work queue,
3443 * then put us on.
3444 */
3445 node->nd_flags |= NGF_WORKQ;
3446 NG_WORKLIST_LOCK();
3447 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work);
3448 NG_WORKLIST_UNLOCK();
3449 NG_NODE_REF(node); /* XXX fafe in mutex? */
3450 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__,
3451 node->nd_ID, node);
3452 } else
3453 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist",
3454 __func__, node->nd_ID, node);
3455 schednetisr(NETISR_NETGRAPH);
3456 }
3457
3458
3459 /***********************************************************************
3460 * Externally useable functions to set up a queue item ready for sending
3461 ***********************************************************************/
3462
3463 #ifdef NETGRAPH_DEBUG
3464 #define ITEM_DEBUG_CHECKS \
3465 do { \
3466 if (NGI_NODE(item) ) { \
3467 printf("item already has node"); \
3468 kdb_enter("has node"); \
3469 NGI_CLR_NODE(item); \
3470 } \
3471 if (NGI_HOOK(item) ) { \
3472 printf("item already has hook"); \
3473 kdb_enter("has hook"); \
3474 NGI_CLR_HOOK(item); \
3475 } \
3476 } while (0)
3477 #else
3478 #define ITEM_DEBUG_CHECKS
3479 #endif
3480
3481 /*
3482 * Put mbuf into the item.
3483 * Hook and node references will be removed when the item is dequeued.
3484 * (or equivalent)
3485 * (XXX) Unsafe because no reference held by peer on remote node.
3486 * remote node might go away in this timescale.
3487 * We know the hooks can't go away because that would require getting
3488 * a writer item on both nodes and we must have at least a reader
3489 * here to be able to do this.
3490 * Note that the hook loaded is the REMOTE hook.
3491 *
3492 * This is possibly in the critical path for new data.
3493 */
3494 item_p
3495 ng_package_data(struct mbuf *m, int flags)
3496 {
3497 item_p item;
3498
3499 if ((item = ng_getqblk(flags)) == NULL) {
3500 NG_FREE_M(m);
3501 return (NULL);
3502 }
3503 ITEM_DEBUG_CHECKS;
3504 item->el_flags = NGQF_DATA | NGQF_READER;
3505 item->el_next = NULL;
3506 NGI_M(item) = m;
3507 return (item);
3508 }
3509
3510 /*
3511 * Allocate a queue item and put items into it..
3512 * Evaluate the address as this will be needed to queue it and
3513 * to work out what some of the fields should be.
3514 * Hook and node references will be removed when the item is dequeued.
3515 * (or equivalent)
3516 */
3517 item_p
3518 ng_package_msg(struct ng_mesg *msg, int flags)
3519 {
3520 item_p item;
3521
3522 if ((item = ng_getqblk(flags)) == NULL) {
3523 NG_FREE_MSG(msg);
3524 return (NULL);
3525 }
3526 ITEM_DEBUG_CHECKS;
3527 /* Messages items count as writers unless explicitly exempted. */
3528 if (msg->header.cmd & NGM_READONLY)
3529 item->el_flags = NGQF_MESG | NGQF_READER;
3530 else
3531 item->el_flags = NGQF_MESG | NGQF_WRITER;
3532 item->el_next = NULL;
3533 /*
3534 * Set the current lasthook into the queue item
3535 */
3536 NGI_MSG(item) = msg;
3537 NGI_RETADDR(item) = 0;
3538 return (item);
3539 }
3540
3541
3542
3543 #define SET_RETADDR(item, here, retaddr) \
3544 do { /* Data or fn items don't have retaddrs */ \
3545 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \
3546 if (retaddr) { \
3547 NGI_RETADDR(item) = retaddr; \
3548 } else { \
3549 /* \
3550 * The old return address should be ok. \
3551 * If there isn't one, use the address \
3552 * here. \
3553 */ \
3554 if (NGI_RETADDR(item) == 0) { \
3555 NGI_RETADDR(item) \
3556 = ng_node2ID(here); \
3557 } \
3558 } \
3559 } \
3560 } while (0)
3561
3562 int
3563 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr)
3564 {
3565 hook_p peer;
3566 node_p peernode;
3567 ITEM_DEBUG_CHECKS;
3568 /*
3569 * Quick sanity check..
3570 * Since a hook holds a reference on it's node, once we know
3571 * that the peer is still connected (even if invalid,) we know
3572 * that the peer node is present, though maybe invalid.
3573 */
3574 if ((hook == NULL)
3575 || NG_HOOK_NOT_VALID(hook)
3576 || (NG_HOOK_PEER(hook) == NULL)
3577 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))
3578 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) {
3579 NG_FREE_ITEM(item);
3580 TRAP_ERROR();
3581 return (ENETDOWN);
3582 }
3583
3584 /*
3585 * Transfer our interest to the other (peer) end.
3586 */
3587 peer = NG_HOOK_PEER(hook);
3588 NG_HOOK_REF(peer);
3589 NGI_SET_HOOK(item, peer);
3590 peernode = NG_PEER_NODE(hook);
3591 NG_NODE_REF(peernode);
3592 NGI_SET_NODE(item, peernode);
3593 SET_RETADDR(item, here, retaddr);
3594 return (0);
3595 }
3596
3597 int
3598 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr)
3599 {
3600 node_p dest = NULL;
3601 hook_p hook = NULL;
3602 int error;
3603
3604 ITEM_DEBUG_CHECKS;
3605 /*
3606 * Note that ng_path2noderef increments the reference count
3607 * on the node for us if it finds one. So we don't have to.
3608 */
3609 error = ng_path2noderef(here, address, &dest, &hook);
3610 if (error) {
3611 NG_FREE_ITEM(item);
3612 return (error);
3613 }
3614 NGI_SET_NODE(item, dest);
3615 if ( hook) {
3616 NG_HOOK_REF(hook); /* don't let it go while on the queue */
3617 NGI_SET_HOOK(item, hook);
3618 }
3619 SET_RETADDR(item, here, retaddr);
3620 return (0);
3621 }
3622
3623 int
3624 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr)
3625 {
3626 node_p dest;
3627
3628 ITEM_DEBUG_CHECKS;
3629 /*
3630 * Find the target node.
3631 */
3632 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */
3633 if (dest == NULL) {
3634 NG_FREE_ITEM(item);
3635 TRAP_ERROR();
3636 return(EINVAL);
3637 }
3638 /* Fill out the contents */
3639 NGI_SET_NODE(item, dest);
3640 NGI_CLR_HOOK(item);
3641 SET_RETADDR(item, here, retaddr);
3642 return (0);
3643 }
3644
3645 /*
3646 * special case to send a message to self (e.g. destroy node)
3647 * Possibly indicate an arrival hook too.
3648 * Useful for removing that hook :-)
3649 */
3650 item_p
3651 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg)
3652 {
3653 item_p item;
3654
3655 /*
3656 * Find the target node.
3657 * If there is a HOOK argument, then use that in preference
3658 * to the address.
3659 */
3660 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) {
3661 NG_FREE_MSG(msg);
3662 return (NULL);
3663 }
3664
3665 /* Fill out the contents */
3666 item->el_flags = NGQF_MESG | NGQF_WRITER;
3667 item->el_next = NULL;
3668 NG_NODE_REF(here);
3669 NGI_SET_NODE(item, here);
3670 if (hook) {
3671 NG_HOOK_REF(hook);
3672 NGI_SET_HOOK(item, hook);
3673 }
3674 NGI_MSG(item) = msg;
3675 NGI_RETADDR(item) = ng_node2ID(here);
3676 return (item);
3677 }
3678
3679 /*
3680 * Send ng_item_fn function call to the specified node.
3681 */
3682
3683 int
3684 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2)
3685 {
3686
3687 return ng_send_fn1(node, hook, fn, arg1, arg2, NG_NOFLAGS);
3688 }
3689
3690 int
3691 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2,
3692 int flags)
3693 {
3694 item_p item;
3695
3696 if ((item = ng_getqblk(flags)) == NULL) {
3697 return (ENOMEM);
3698 }
3699 item->el_flags = NGQF_FN | NGQF_WRITER;
3700 NG_NODE_REF(node); /* and one for the item */
3701 NGI_SET_NODE(item, node);
3702 if (hook) {
3703 NG_HOOK_REF(hook);
3704 NGI_SET_HOOK(item, hook);
3705 }
3706 NGI_FN(item) = fn;
3707 NGI_ARG1(item) = arg1;
3708 NGI_ARG2(item) = arg2;
3709 return(ng_snd_item(item, flags));
3710 }
3711
3712 /*
3713 * Send ng_item_fn2 function call to the specified node.
3714 *
3715 * If an optional pitem parameter is supplied, its apply
3716 * callback will be copied to the new item. If also NG_REUSE_ITEM
3717 * flag is set, no new item will be allocated, but pitem will
3718 * be used.
3719 */
3720 int
3721 ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn, void *arg1,
3722 int arg2, int flags)
3723 {
3724 item_p item;
3725
3726 KASSERT((pitem != NULL || (flags & NG_REUSE_ITEM) == 0),
3727 ("%s: NG_REUSE_ITEM but no pitem", __func__));
3728
3729 /*
3730 * Allocate a new item if no supplied or
3731 * if we can't use supplied one.
3732 */
3733 if (pitem == NULL || (flags & NG_REUSE_ITEM) == 0) {
3734 if ((item = ng_getqblk(flags)) == NULL)
3735 return (ENOMEM);
3736 } else
3737 item = pitem;
3738
3739 item->el_flags = NGQF_FN2 | NGQF_WRITER;
3740 NG_NODE_REF(node); /* and one for the item */
3741 NGI_SET_NODE(item, node);
3742 if (hook) {
3743 NG_HOOK_REF(hook);
3744 NGI_SET_HOOK(item, hook);
3745 }
3746 NGI_FN2(item) = fn;
3747 NGI_ARG1(item) = arg1;
3748 NGI_ARG2(item) = arg2;
3749 if (pitem != NULL && (flags & NG_REUSE_ITEM) == 0)
3750 item->apply = pitem->apply;
3751 return(ng_snd_item(item, flags));
3752 }
3753
3754 /*
3755 * Official timeout routines for Netgraph nodes.
3756 */
3757 static void
3758 ng_callout_trampoline(void *arg)
3759 {
3760 item_p item = arg;
3761
3762 ng_snd_item(item, 0);
3763 }
3764
3765
3766 int
3767 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
3768 ng_item_fn *fn, void * arg1, int arg2)
3769 {
3770 item_p item, oitem;
3771
3772 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL)
3773 return (ENOMEM);
3774
3775 item->el_flags = NGQF_FN | NGQF_WRITER;
3776 NG_NODE_REF(node); /* and one for the item */
3777 NGI_SET_NODE(item, node);
3778 if (hook) {
3779 NG_HOOK_REF(hook);
3780 NGI_SET_HOOK(item, hook);
3781 }
3782 NGI_FN(item) = fn;
3783 NGI_ARG1(item) = arg1;
3784 NGI_ARG2(item) = arg2;
3785 oitem = c->c_arg;
3786 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 &&
3787 oitem != NULL)
3788 NG_FREE_ITEM(oitem);
3789 return (0);
3790 }
3791
3792 /* A special modified version of untimeout() */
3793 int
3794 ng_uncallout(struct callout *c, node_p node)
3795 {
3796 item_p item;
3797 int rval;
3798
3799 KASSERT(c != NULL, ("ng_uncallout: NULL callout"));
3800 KASSERT(node != NULL, ("ng_uncallout: NULL node"));
3801
3802 rval = callout_stop(c);
3803 item = c->c_arg;
3804 /* Do an extra check */
3805 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) &&
3806 (NGI_NODE(item) == node)) {
3807 /*
3808 * We successfully removed it from the queue before it ran
3809 * So now we need to unreference everything that was
3810 * given extra references. (NG_FREE_ITEM does this).
3811 */
3812 NG_FREE_ITEM(item);
3813 }
3814 c->c_arg = NULL;
3815
3816 return (rval);
3817 }
3818
3819 /*
3820 * Set the address, if none given, give the node here.
3821 */
3822 void
3823 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr)
3824 {
3825 if (retaddr) {
3826 NGI_RETADDR(item) = retaddr;
3827 } else {
3828 /*
3829 * The old return address should be ok.
3830 * If there isn't one, use the address here.
3831 */
3832 NGI_RETADDR(item) = ng_node2ID(here);
3833 }
3834 }
3835
3836 #define TESTING
3837 #ifdef TESTING
3838 /* just test all the macros */
3839 void
3840 ng_macro_test(item_p item);
3841 void
3842 ng_macro_test(item_p item)
3843 {
3844 node_p node = NULL;
3845 hook_p hook = NULL;
3846 struct mbuf *m;
3847 struct ng_mesg *msg;
3848 ng_ID_t retaddr;
3849 int error;
3850
3851 NGI_GET_M(item, m);
3852 NGI_GET_MSG(item, msg);
3853 retaddr = NGI_RETADDR(item);
3854 NG_SEND_DATA(error, hook, m, NULL);
3855 NG_SEND_DATA_ONLY(error, hook, m);
3856 NG_FWD_NEW_DATA(error, item, hook, m);
3857 NG_FWD_ITEM_HOOK(error, item, hook);
3858 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr);
3859 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr);
3860 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr);
3861 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr);
3862 }
3863 #endif /* TESTING */
3864
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